President Trump, on his third day of hospitalization for the coronavirus, briefly visited well-wishers gathered outside Walter Reed National Military Medical Center during a drive-by in a sport utility vehicle with two Secret Service agents on Sunday evening, in apparent disregard of federal safety guidelines.
In a video posted moments earlier on his Twitter account, Mr. Trump, his voice a bit husky but otherwise normal, tried to project the image of a man on the mend, saying he was getting “great reports from the doctors.”
The president, whose mishandling of the pandemic has become a political liability, also said his first-person experience with a deadly infection that had cost the lives of more than 200,000 Americans had changed his perspective on the crisis. He did not specify how.
“It’s been a very interesting journey; I learned a lot about Covid,” Mr. Trump said in the video. “I learned it by really going to school. This is the real school, this isn’t the let’s-read-the-book school. And I get it, and I understand it, and it’s a very interesting thing, and I’m going to be letting you know about it. In the meantime, we love the U.S.A., and we love what’s happening.”
He sat in the back of the vehicle, wearing a black cloth mask, sitting behind at least two Secret Service agents. Face coverings are a safeguard — and the N95 masks the agents seemed to be wearing are an especially effective barrier — but they are not an absolute guarantee of stopping transmission, especially in a small enclosed space occupied by a person known to be infected.
It was not clear if there was a partition in the S.U.V.
“Appropriate precautions were taken in the execution of this movement to protect the President and all those supporting it, including PPE,” Judd Deere, a White House spokesman, said in an email Sunday night. “The movement was cleared by the medical team as safe to do.”
Secret Service officers accompanied Mr. Trump to the hospital on Friday, but that was an emergency situation; Sunday’s drive was a “last-minute” decision by the president, Deere told reporters.
The Centers for Disease Control and Prevention guidelines for patients infected with the virus stipulate that health care facilities “limit transport and movement of the patient outside of the room to medically essential purposes.”
The president’s foray outside the hospital walls came at the end of a weekend of concern and confusion about his condition, some of it sown by his own doctors, who gave conflicting accounts. Their version of events on Sunday was that Mr. Trump’s blood-oxygen levels had dropped enough to require oxygen to be administered to him at least once, and that he was being given the steroid dexamethasone, which is usually used only for severely ill Covid patients, but that he was doing well and could be released as soon as Monday.
Mr. Trump returned to the hospital’s presidential suite after his brief excursion, White House officials told the media. The trip quickly drew scrutiny online and raised questions about whether it had breached medical protocols.
“That Presidential SUV is not only bulletproof, but hermetically sealed against chemical attack,” Dr. James P. Phillips, whose profile on Doximity, a professional network for doctors, lists him as an emergency medicine physician affiliated with Walter Reed, wrote on Twitter.
“The risk of COVID19 transmission inside is as high as it gets outside of medical procedures. The irresponsibility is astounding. My thoughts are with the Secret Service forced to play.”
Dr. Phillips, whose Twitter profile lists him as the chief of disaster and operational medicine at George Washington University, tweeted that every person riding in the S.U.V. with Mr. Trump needed to quarantine for 14 days.
“They may die,” Dr. Phillips wrote. “For political theater. Commanded by Trump to put their lives at risk for theater. This is insanity.”
Not everyone was skeptical. Mr. Trump’s supporters, lining the sidewalk in front of the hospital gates, let out a collective whoop of “We love Trump!” as the president’s motorcade slow-rolled past.
“God bless our president — I will die for him. I will die for that man happily!” shouted a man in the crowd, according to audio and video posted by C-SPAN.
Even with President Trump still hospitalized for Covid-19 on Sunday, officials on his campaign continued to defend his flouting of public health guidelines and refused to acknowledge that it could have led to his infection and the infections of other Republicans.
Steve Cortes, a senior adviser to Mr. Trump’s campaign, said on “Fox News Sunday” that the president and his associates had taken “tremendous precautions” to avoid the virus, even though Mr. Trump is rarely seen wearing a mask and has held large, and largely mask-free, events in violation of public health recommendations.
Another Trump campaign aide, Jason Miller, made similarly misleading remarks on NBC’s “Meet the Press,” describing Mr. Trump as “the single most protected person on the entire planet” without mentioning the precautions the president has often rejected.
Mr. Cortes outlined a false choice, suggesting that the alternative to holding large events without masks was to remain “hermetically sealed” in the White House. He added that the president had been “unwilling to completely sequester himself, to take no risk, because leaders take risks,” and went on to argue that Mr. Trump’s illness showed the futility of protective measures — many of which the president did not actually take.
Health officials are clear that masks are crucial to controlling the virus. The director of the Centers for Disease Control and Prevention told senators last month that masks might be even more important than a vaccine.
In a remarkable exchange with the Fox News host Chris Wallace, Mr. Cortes defended the refusal of Mr. Trump’s family members to wear masks at Tuesday’s debate, which Mr. Wallace moderated. Mr. Cortes insisted that masks had been unnecessary because the family tested negative before the debate — even though Mr. Trump and his wife, Melania, later tested positive, and even though health officials had explicitly mandated masks regardless of test results.
WALLACE: Everybody was told to wear a mask. Why did the first family and the chief of staff feel that the rules for everybody else didn’t apply to them?
CORTES: Chris, we believe that masks are very useful. The president has worn them on many occasions, including visiting the hospital where he is now a patient — when he was visiting as commander in chief, as a guest to visit soldiers there, he wore a mask. We believe in masks. We also believe in some element of individual choice. People were distanced and they had been tested.
WALLACE: They weren’t distanced and there were rules and there was no freedom of choice. They broke the rules. Why did they break the rules?
CORTES: Look, those chairs were not close together, and again, we also believe that —
WALLACE: It doesn’t matter. They were close together, Steve, and the rules from the Cleveland Clinic were everybody wears a mask. Why didn’t they?
CORTES: Chris, the way you’re starting to harangue me now actually reminds me of what you did to the president during that debate on Tuesday night.
On ABC’s “This Week,” Mr. Miller continued to mock Joseph R. Biden Jr. for wearing masks.
“Too often he’s used the mask as a prop,” Mr. Miller said. “Masks are very important, but he could be 20, 30 feet away from the nearest person and still have the mask on. That’s not going to change anything that’s out there. But also, we’ve seen with Joe Biden — I mean, we can’t all just stay in our basement for the rest of our lives.”
Mr. Biden has continued traveling for in-person campaigning while Mr. Trump is hospitalized.
Donald J. Trump has told aides to think of every day of his administration as an episode in a television show.
That production, it turns out, does not take sick days.
The president’s diagnosis and treatment for Covid-19 has unfolded as TV drama, some of it stunning, some baffling — and some of it crafted by Mr. Trump’s own producers, in a surreal but characteristic attempt to try to wrangle control of reality through pictures.
On Sunday evening, viewers saw a striking image of Mr. Trump inside a black sport utility vehicle waving to supporters who had gathered outside of Walter Reed National Military Medical Center.
Moments earlier, he had posted a video on Twitter of himself standing inside the hospital and telling viewers that he had received “great reports” from doctors on his condition.
The treatment of the president for a potentially deadly disease would, for any administration, be a public-relations challenge as well as a health crisis. But that’s exponentially more so for a reality-TV celebrity who has built his political image on claims, however questionable, of machismo, vitality and vigor.
Now, in the last month of a re-election campaign, he was hobbled by the very pandemic that he had notoriously played down. How badly hobbled was no clearer after a bobbing-and-weaving on-camera press briefing Saturday by the White House physician, Dr. Sean P. Conley.
Hours later, instead of clarity on Mr. Trump’s health, we got more pictures. Saturday evening on Twitter, Mr. Trump posted a new video, seated open-collared and maskless at a table with neatly arranged binders and papers. Later that night, the White House released more official images of Mr. Trump soberly looking at the same array of papers in two different rooms.
It is not clear what paper Mr. Trump was signing in one photo or if the papers were in fact even official documents. But you could not dispute that he was at work, because for this president, creating images has always been the work.
Joseph R. Biden Jr. has again tested negative for the coronavirus, his campaign announced Sunday evening, less than a week after he shared a debate stage with President Trump, who has tested positive for the virus and is in the hospital.
Mr. Biden, 77, who intends to travel to Florida on Monday, had said that he would be tested Sunday morning.
“Vice President Biden underwent PCR testing for Covid-19 today and Covid-19 was not detected,” read a campaign statement distributed by a pool reporter.
Mr. Biden also tested negative twice on Friday following news of Mr. Trump’s positive test, a campaign spokesman, Andrew Bates, said.
His campaign has declined to specify exactly how often Mr. Biden will be tested, though the Democratic nominee told reporters Saturday that he had not been tested that day, suggesting that he is not being tested daily.
On Sunday morning, Symone D. Sanders, a senior adviser to the campaign, said on CNN that Mr. Biden would be tested before traveling.
Until recently, the Biden campaign had said it would release the results of a confirmed case of Covid-19, but in a Saturday night statement — facing mounting questions about testing protocol — the campaign said it would release the results of each test.
President Trump’s medical team acknowledged on Sunday that they had delivered an overly rosy description of the president’s illness on Saturday.
“I didn’t want to give any information that might steer the course of illness in another direction, and in doing so, you know, it came off that we were trying to hide something, which wasn’t necessarily true,” Dr. Sean P. Conley, the White House physician, said in a briefing with reporters.
The doctors said that on Friday, Mr. Trump had a “high fever” and that his blood oxygen level dropped, requiring him to be administered oxygen. They said his oxygen level dropped again on Saturday but were not clear on whether he was administered oxygen again.
Dr. Conley said that the president had also been given the steroid dexamethasone on Saturday, which has been shown to help patients who are severely ill with Covid-19, but is typically not used in mild or moderate cases of the disease.
Nonetheless, the doctors said, Mr. Trump is doing better, and they projected he could be discharged as early as Monday. The briefing came a day after a messy and conflicting presentation from the doctors about whether Mr. Trump had serious medical issues on Friday.
Dr. Conley announced on Saturday that the president was “doing great.” But moments later, the president’s chief of staff, Mark Meadows, offered a contradictory assessment, noting “the president’s vitals over the last 24 hours were very concerning, and the next 48 hours will be critical in terms of his care.”
“We’re still not on a clear path to a full recovery,” he added.
Mr. Trump posted a video to Twitter on Saturday evening, offering his own account of his health. “I’m starting to feel good,” he said, adding, “We’ll be seeing what happens over those next couple of days.”
Vice President Mike Pence, who would be the most powerful man in the nation should President Trump become too ill to continue his duties, has been on the campaign trail despite having been in close contact with the president and being at high risk of having the virus himself.
“There is no way under the sun that Pence should be anywhere but in his home,” said Dr. Rochelle Walensky, an infectious disease expert at Harvard University. “He was sitting in a sea of people with Covid; there is no way he should go anywhere.”
Though Mr. Pence has tested negative each of the last three days, it is possible to test negative and still be infected early in the course of the virus.
Mr. Pence was last in contact with the president on Tuesday morning at the White House. He may have also been in close contact with several others who tested positive after having attended the White House event last Saturday to celebrate the nomination of Judge Amy Coney Barrett. Mr. Trump began feeling symptoms as early as Wednesday, and several studies have shown that people are most infectious from one to two days before showing symptoms to about two days after. This could mean that Mr. Trump was already highly infectious on Tuesday.
And it puts Mr. Pence and anyone who came into contact with Mr. Trump on Tuesday squarely at risk. Chris Christie, the former governor of New Jersey, who helped the president at the White House with debate preparation from last Saturday through Tuesday, has tested positive.
Former Vice President Joseph R. Biden Jr. is also at risk of being infected, experts say. Although he and Mr. Trump stood more than 12 feet apart at the debate, they were indoors. Studies have shown that indoors, the virus can travel farther than six feet, prompting experts to recommend that Mr. Biden also quarantine and get tested daily.
Mr. Biden has continued to campaign, traveling to Grand Rapids, Mich., on Friday, and holding a virtual town hall with a union on Saturday. He is usually seen wearing a mask at campaign events.
Mr. Pence, meanwhile, has traveled to several states and participated in outdoor and indoor campaign events. On Wednesday, he attended a packed fund-raiser in Atlanta, and on Thursday spoke at two indoor events in Iowa. He did not wear a mask on either day; nor did most attendees.
Mr. Pence’s team has said that he tested negative for the coronavirus on Friday, Saturday and Sunday. But tests for the virus can produce false negatives if used too early in the course of infection. The virus can take up to 14 days to show symptoms, which is why the Centers for Disease Control and Prevention recommends that anyone who has been in close contact with an infected person quarantine for 14 days.
Trump campaign officials said Sunday that Mr. Pence had no plans to curtail his public appearances. “He will be hitting the trail,” Jason Miller, the campaign’s senior adviser, told CNN. “And he’s going to have a very full, aggressive schedule.”
He is scheduled to hold a rally at a police-equipment manufacturer in Arizona on Thursday. His vice-presidential debate against Kamala Harris, on Wednesday in Utah, is also still on.
Donald McNeil Jr. contributed reporting.
Joseph R. Biden Jr. plans to travel to Florida on Monday, brushing aside suggestions that he curtail his campaign appearances until he is certain that he did not contract the coronavirus after sharing a debate stage with President Trump last week.
Medical experts have said it is likely that Mr. Trump was contagious during his debate with Mr. Biden on Tuesday. Centers for Disease Control and Prevention guidelines call for 14 days of quarantine for anyone exposed to the virus.
Mr. Biden tested negative once again on Sunday, and his campaign said he was being tested before each trip, but tests are not always reliable in the early stages of an infection. The campaign promised to make the results of each test public.
On Sunday afternoon, the Biden campaign said that Mr. Biden and his wife, Jill Biden, planned to visit the Little Haiti Cultural Center in Miami, then deliver remarks on the economy in the city’s Little Havana neighborhood.
Mr. Biden also plans to participate in an outdoor NBC News town hall in Miami in the evening, campaign officials said.
Symone Sanders, a senior adviser to Mr. Biden, emphasized on CNN that he and members of his campaign staff were wearing masks, holding most events outdoors, enforcing social distancing and taking other precautions, and said that because he had been “well over six feet away” from Mr. Trump, “Vice President Biden was not exposed.”
But while six feet is a rule of thumb, it is not a definitive line beyond which there is no risk of exposure. Researchers have established that the virus can travel farther than six feet, particularly indoors.
Juliet Morrison, a virologist at the University of California, Riverside, said that given his proximity to Mr. Trump at a time when the president was probably infectious, Mr. Biden should quarantine.
“The most responsible thing to do in this situation is to just wait and see,” Dr. Morrison said. “And in the meantime, treat yourself as if you are infected.”
Ms. Sanders and Kate Bedingfield, Mr. Biden’s deputy campaign manager, both said they hoped the next presidential debate, scheduled for Oct. 15 in Miami, could be held safely.
“We hope that they’re going to put in place every adjustment necessary to ensure that it’s fully safe,” Ms. Bedingfield said on ABC, referring to the commission organizing the debates. “And obviously we send President Trump our best. We hope that he is well and able to debate. If he is, Joe Biden will certainly be there.”
Evangelical Christians helped propel Donald J. Trump to victory in 2016 and have had his ear ever since, especially as some of them clashed with blue-state governors earlier this year over pandemic restrictions on in-person religious services.
On Sunday, a group of evangelical leaders led a virtual vigil for Mr. Trump and the first lady, Melania Trump, both of whom have been infected with the coronavirus.
The prayer call, organized by the Trump campaign and hosted by Lara Trump, who is married to Eric Trump, the president’s middle son, was broadcast on Facebook Live. It was led by Paula White-Cain, a Florida televangelist who officiated at Mr. Trump’s inauguration and is an adviser to the president; Cissie Graham Lynch, a granddaughter of the preacher Billy Graham; and three other evangelical leaders.
The vigil came as President Trump remained hospitalized at Walter Reed National Military Medical Center for treatment of the virus, the threat of which he had consistently played down since the start of the pandemic.
“Mr. President, you are very, very loved,” Rev. Ramiro A. Peña, a senior pastor of Christ the King Church of Waco, Texas, said during the vigil. “We unite and come against Covid-19. We say, ‘You cease and desist right now in the name of Jesus. Lord, we say, put a stop to it.’”
Nearly 210,000 Americans have died from the virus, something critics of Mr. Trump’s handling of the crisis emphasized on Sunday as the Trump campaign and evangelical leaders promoted the call to prayer. Some questioned whether the campaign had gone to similar efforts for others lost to the virus.
Tim Murtaugh, a Trump campaign spokesman, said on Sunday that there had been regular prayer calls for the entire nation since March.
“There has been a consistent effort over the last six months to call on people to pray,” Mr. Murtaugh said.
In May, Mr. Trump pushed for states to allow places of worship to reopen “right away” and threatened to override the emergency orders of governors who defied him, though it was not clear under what authority he could do so.
At one point during the Facebook Live vigil, more than 50,000 viewers were watching.
Ms. Graham Lynch said that the pandemic had demonstrated the fragility of life and that it was beyond Mr. Trump’s control to bring an end to the suffering.
“I pray that our president would know that he is not truly alone,” she said, appealing to God. “No politician, no Republican, no Democrat can bring healing to this nation. Only you can.”
Joseph R. Biden Jr. leads President Trump by double digits in two national polls released Sunday, one conducted after the presidential debate but before Mr. Trump announced that he had the coronavirus, and one conducted after his announcement.
An NBC News/Wall Street Journal poll, conducted Wednesday and Thursday after the debate, found that 53 percent of registered voters planned to vote for Mr. Biden and 39 percent for Mr. Trump, with a margin of error of plus or minus 3.5 percentage points. The 14-point lead is the largest Mr. Biden has had in any NBC/Wall Street Journal poll this year.
Mr. Biden benefited from huge leads among older voters (62 percent to 35 percent) and suburban women (58 percent to 33 percent). In 2016, most older voters voted for Mr. Trump over Hillary Clinton, exit polls found.
The second poll, conducted by Reuters and Ipsos on Friday and Saturday, after the president said he had the virus, showed Mr. Biden leading Mr. Trump by 10 points, 51 percent to 41 percent, with a margin of error of plus or minus five percentage points.
Sixty-five percent of respondents in the Reuters/Ipsos poll agreed with the statement, “If Mr. Trump had taken coronavirus more seriously, he probably would not have been infected.” That included roughly nine in 10 registered Democrats and about half of registered Republicans.
In a third poll, by ABC News and Ipsos, 72 percent of respondents said Mr. Trump had not taken the risk of contracting Covid-19 seriously enough; the same number said he had not taken “the appropriate precautions when it came to his personal health.” That poll did not ask about the election.
Mr. Trump has flouted public health guidelines for months, continuing to hold large rallies — including some indoors, where the risk of transmission is higher — and almost never wearing a mask. At the presidential debate last week, during which he may already have been infected, he mocked Mr. Biden for wearing a mask.
Notably, since the announcement that Mr. Trump was infected, Republicans and independents appear to have become much more concerned that they or someone they know will contract the virus.
Seventy percent of Republicans in the ABC News poll said they were concerned, up from 52 percent just two weeks ago, and 82 percent of independents said they were concerned, up from 69 percent. Among Democrats, the number was unchanged at 86 percent.
President Trump’s national security adviser said on Sunday that he had warned his Russian counterpart last week that “there would be absolutely no tolerance for any interference” in the November election, but did not mention that American intelligence officials and a range of private firms had said they already saw evidence of Russian influence operations.
The adviser, Robert C. O’Brien, said on CBS’s “Face the Nation” that he had delivered the warning during a meeting in Geneva on Friday with Nikolai Patrushev, the secretary of Russia’s Security Council. Mr. O’Brien did not disclose what else was discussed, but the meeting comes as the administration is racing a deadline to decide whether to extend the New START nuclear arms control treaty and as it faces pressure to act against Moscow after the poisoning of Aleksei Nalvany, the Russian opposition leader.
“One of the reasons I went to meet with General Patrushev is to let him know that there would be absolutely no tolerance for any interference with our Election Day, with our voting, with the vote tallies, and demanded that — that Russia not engage in that sort of thing,” he said, failing to mention the key way Russia had interfered, with a sophisticated disinformation campaign.
“The Russians have committed to doing so,” he said. “And so, look, it’s Russia. So, as President Reagan said and as President Trump often says, it’s trust, but verify.”
American intelligence agencies have already found the Russians to be active in the 2020 election. Christopher A. Wray, the F.B.I. director, told Congress in September that “the intelligence community consensus is that Russia continues to try to influence our elections.” Microsoft has provided similar evidence, as have Facebook and other social media firms.
Senator Patrick J. Toomey, a Pennsylvania Republican, will not seek re-election in 2022, vacating a battleground-state race more than two years before he leaves office.
Mr. Toomey, 58, last week informed Senator Mitch McConnell, the majority leader, of his decision not to seek a third term, according to a person familiar with their conversation. The Philadelphia Inquirer, which broke the news of Mr. Toomey’s decision, reported that he would also not run for governor of Pennsylvania in 2022.
Mr. Toomey’s spokesman, Steve Kelly, declined to comment on his decision but said that Mr. Toomey would make an announcement Monday morning.
A fiscal and social conservative who was president of the hard-right Club for Growth before his 2010 Senate campaign, Mr. Toomey carved out a niche as a rare Republican willing to entertain gun control proposals like expanded background checks.
In 2013, he partnered with Senator Joe Manchin, a West Virginia Democrat, to put forward background-check legislation after the Sandy Hook school massacre in Connecticut. The bill failed, and the Senate has not considered significant gun control legislation since.
Mr. Toomey’s decision to not seek re-election complicates what was already shaping up to be a tough 2022 map for Republicans. The timing of his announcement, one month before the 2020 general election that has consumed political attention in Pennsylvania, came a surprise.
“It takes away our best candidate,” Rob Gleason, a former chairman of the Pennsylvania Republican Party, said of Mr. Toomey’s decision. “It throws it pretty wide open for sure.”
Along with the now-open seat in Pennsylvania, the party will be defending seats likely to be competitive in Florida, Iowa, North Carolina, Ohio and Wisconsin — all battlegrounds in the current presidential campaign.
Democrats will be defending far fewer likely competitive seats — in Colorado, New Hampshire and Nevada.
The winner of Arizona’s 2020 Senate race to complete the remainder of Senator John McCain’s term, between Senator Martha McSally, a Republican, and former astronaut Mark Kelly, a Democrat, will also be up for re-election to a full six-year term in 2022.
A short-handed Supreme Court — driven from its courtroom by the pandemic, grieving over the loss of a colleague and awaiting the outcome of a divisive confirmation battle — will return to the virtual bench on Monday to start a term that will present Chief Justice John G. Roberts Jr. with a daunting test.
“The chief’s leadership of the court, which just a few weeks ago appeared to be at its zenith, is now in peril,” said Richard J. Lazarus, a law professor at Harvard who has taught courses on the Supreme Court with Chief Justice Roberts. “An addition of yet another very conservative justice could quickly eliminate the chief’s ability to steer the court toward moderation.”
The court will again hear arguments by telephone, starting with a timely case on the role of partisanship in judging, a subject that will also figure in Senate hearings on the Supreme Court nomination of Judge Amy Coney Barrett, which are scheduled to start a week from Monday. President Trump and Senate Republicans have been working hard to speed her path to the seat left vacant by the death of Justice Ruth Bader Ginsburg.
A court that includes Judge Barrett would thrust Chief Justice Roberts from his spot at the court’s ideological center and empower Mr. Trump’s three appointees — Judge Barrett, and Justices Neil M. Gorsuch and Brett M. Kavanaugh, said Lee Epstein, a law professor and political scientist at Washington University in St. Louis.
If Judge Barrett is confirmed before Election Day, she is expected to participate in the two biggest arguments on the docket so far: the latest challenge to the Affordable Care Act and a clash between claims of religious freedom and gay rights in the context of foster care.
Justice Ginsburg would almost certainly have voted to uphold the health care law and government programs that prohibit discrimination against gay couples. Judge Barrett’s votes in those cases could provide a telling early sense of how her appointment could shift the direction of the court.
The term that ended in July included a few liberal surprises in cases on abortion, immigration and L.G.B.T. rights. It also included the rejection of Mr. Trump’s categorical claims that he could defy subpoenas for his financial returns, and a string of victories for religious groups. Chief Justice Roberts was in the majority in all of those cases, and he dissented only twice in argued cases in the entire term.
Joe Biden leads Donald Trump in Florida and Pennsylvania. Both states are crucial to Mr. Trump’s re-election chances.
|2016 Election Result||NYT/Siena
Based on New York Times/Siena College polls of 710 likely voters in Florida from Sept. 30 to Oct. 1 and 706 likely voters in Pennsylvania from Sept. 30 to Oct. 2.
By overwhelming margins, voters in Pennsylvania and Florida were turned off by President Trump’s conduct in the first general election debate, according to New York Times/Siena College surveys, as Joseph R. Biden Jr. maintained a lead in the two largest battleground states.
Over all, Mr. Biden led by seven percentage points, 49 percent to 42 percent, among likely voters in Pennsylvania. He led by a similar margin, 47-42, among likely voters in Florida.
The surveys began Wednesday, before the early Friday announcement that Mr. Trump had contracted the coronavirus. There was modest evidence of a shift in favor of Mr. Biden in interviews on Friday, including in Arizona where a Times/Siena survey is in progress, after controlling for the demographic and political characteristics of the respondents.
One day of interviews is not enough to evaluate the consequences of a major political development, and it may be several days or longer before even the initial effects of Mr. Trump’s diagnosis can be ascertained by pollsters.
The debates long loomed as one of the president’s best opportunities to reshape the race in his favor. He has trailed in Pennsylvania and Florida from the outset of the campaign, and he does not have many credible paths to the presidency without winning at least one of the two — and probably both.
Instead, a mere 22 percent of likely voters across the two pivotal states said Mr. Trump won the debate Tuesday. It leaves the president at a significant and even daunting disadvantage with a month until Election Day.
But while Mr. Trump failed to capitalize on a rare opportunity to claw back into the race, the findings suggest that the debate did not shift the contest decisively in Mr. Biden’s direction, either. The results were close to the average of pre-debate surveys in both states, another reflection of the unusually stable polling results ahead of the election. In Pennsylvania, the race was even somewhat closer than it was in a Times/Siena poll conducted before the debate, which found Mr. Biden ahead by nine percentage points.
The lack of additional gains by Mr. Biden after the first debate might have been all but inevitable in a deeply polarized country. But it might also suggest that Mr. Biden, like the president, failed to capitalize on opportunities of his own.
President Trump’s bombshell announcement early Friday morning that he and the first lady had tested positive for the coronavirus has set off a frenzy in the White House and beyond as politicians and operatives who have interacted with Mr. Trump in recent days have raced to get their own tests and, in some cases, report the results.
Here is a quick look at the people in Mr. Trump’s orbit and beyond who have spoken publicly about their health and the virus, taken from official statements, and announcements made on social media and by spokespersons.
It can take several days after exposure for the virus to reach levels that are detectable by a test. People show symptoms on average around five days after exposure, but as late as 14 days.
Who has tested positive:
Ronna McDaniel, the chairwoman of the Republican National Committee
Hope Hicks, one of Mr. Trump’s most senior advisers
Bill Stepien, President Trump’s campaign manager
Kellyanne Conway, the former top White House adviser, who attended Judge Amy Coney Barrett’s Supreme Court nomination ceremony at the White House on Sept. 26
Senator Thom Tillis of North Carolina, who participated in a debate against his Democratic challenger on Thursday
Rev. John I. Jenkins, the president of the University of Notre Dame, who also attended the ceremony for Judge Barrett last week
Senator Ron Johnson of Wisconsin, who did not attend Judge Barrett’s ceremony last week
The former New Jersey governor Chris Christie, who helped the president prepare for the debate
Nick Luna, the head of Oval Office operations at the White House
Who has tested negative:
Mike Pompeo, the secretary of state
Steven Mnuchin, the Treasury secretary
William P. Barr, the attorney general
Mark Meadows, the White House chief of staff
Dan Scavino, the White House deputy chief of staff
Jared Kushner, Mr. Trump’s son-in-law and senior adviser
Ivanka Trump, Mr. Trump’s daughter
Donald Trump Jr., Mr. Trump’s son
Barron Trump, Mr. Trump’s son
Eric Trump, Mr. Trump’s son
Lara Trump, Eric Trump’s wife
Tom Perez, the chairman of the Democratic National Committee
Betsy DeVos, the education secretary
Senator Ben Sasse, Republican of Nebraska and a member of the Judiciary Committee. He attended Judge Barrett’s ceremony.
Senator Josh Hawley, Republican of Missouri and a member of the Judiciary Committee. He attended Judge Barrett’s ceremony.