Biden Casts Himself as the Trump Beater. Polls Suggest That’s No Sure Thing.

WASHINGTON — Boiled down, President Biden’s argument for running for a second term rather than ceding the ground to the next generation is that he is the Democrat most assured of beating former President Donald J. Trump next year.

But a striking new poll challenged that case in a way that had much of the capital buzzing the last couple of days. Taken at face value, the poll showed Mr. Biden trailing Mr. Trump by six percentage points in a theoretical rematch, raising the question of whether the president is as well positioned as he maintains.

No single poll means all that much, especially so early in an election cycle, and the president’s strategists as well as some independent analysts questioned its methodology. But even if it is an outlier, other recent surveys have indicated that the race is effectively tied, with either Mr. Biden or Mr. Trump holding narrow leads within the margin of error. Taken together, they suggest that the president opens the 2024 campaign facing enormous challenges with no guarantee of victory over Mr. Trump.

The data has left many Democrats feeling anywhere from queasy to alarmed. Mr. Biden’s case for being the pair of safe hands at a volatile moment is undermined in their view if a president who passed major legislation and presides over the lowest unemployment in generations cannot outperform a twice-impeached challenger who instigated an insurrection, has been indicted on multiple felonies, is on civil trial accused of rape and faces more potential criminal charges in the months to come.

“The poll demonstrates that the president still has work to do, not only in convincing the American people that he’s up for the job that he wishes to complete,” said Donna Brazile, a former chairwoman of the Democratic National Committee who said she lost sleep over the “ominous signs” in the latest survey results. “More importantly, it’s a good forecast of the challenges he will face in rebuilding the remarkable coalition that elected him in 2020.”

“I don’t think that they should panic because you can’t panic after one poll,” said Ms. Brazile, who managed Al Gore’s presidential campaign in 2000. A survey is “just one gauge” among many on the long road to the voting booth. “But it’s an important barometer of where the electorate is today, some 547 days away from the November 2024 election.”

The survey by The Washington Post and ABC News found the president’s approval rating at just 36 percent and that Mr. Trump would beat him by 44 percent to 38 percent if the election were held today. Just as worrisome for Democrats, respondents considered Mr. Trump, 76, more physically and mentally fit than Mr. Biden, 80, and concluded that the former president managed the economy better than the incumbent has.

Critics of the poll disparaged it for surveying all adults, rather than registered or likely voters, and maintained that its results among subgroups like young people, independents, Hispanics and Black Americans were simply not credible.

“The poll really is trash, and I don’t say that lightly because I’ve had respect for their polling in the past,” said Cornell Belcher, who was President Barack Obama’s pollster. “However, their methodological decision here is problematic,” he added of the way the survey was constructed.

Others cautioned against overanalyzing data this early, noting that anything can happen in the next 18 months and recalling that projections based on polling — or misinterpretations of polling — proved to be poor predictors in recent cycles, including the 2022 midterm elections when a forecast “red wave” did not materialize.

“Polls in May 2024 will be of dubious value,” said David Plouffe, who was Mr. Obama’s campaign manager. “Polls in May 2023 are worth as much as Theranos stock.”

The White House expressed no concern over the latest surveys, recalling that the president has been underestimated before. “President Biden’s average job approval is higher now than in early November when poll-based reporting widely prophesied a supposedly inevitable red wave that never arrived,” said Andrew Bates, a White House spokesman.

But as a marker at the start of the race, especially comparing two figures universally known by the public, recent surveys provide a foundational baseline foreshadowing a campaign without a clear front-runner. Polls by Yahoo News, The Wall Street Journal and Morning Consult have found the president slightly ahead while surveys by The Economist and the Harvard University Center for American Political Studies found him tied or trailing by several points. Mr. Biden faces similarly mixed results against Gov. Ron DeSantis of Florida, the strongest challenger to Mr. Trump for the Republican nomination.

The results point to a calcification in American politics where the leaders of both parties have a similarly sized core of support among voters not open to the other side regardless of developments in the news. The days when presidents could enjoy approval ratings above 50 percent for any sustained period of time appear to be long over. And so if widespread support is no longer achievable, the challenge for Mr. Biden is to reassemble the coalition that provided him a 4.5-percentage-point victory nearly three years ago.

Mr. Biden has dismissed the importance of polls, saying that he is no different from other presidents at this point in their terms. “Every major one who won re-election, their polling numbers were where mine are now,” he told Stephanie Ruhle on “The 11th Hour” on MSNBC on Friday.

But in fact, only two of the past 13 presidents had approval ratings lower than Mr. Biden has at this point, according to an aggregate compilation by FiveThirtyEight.com — Mr. Trump and Jimmy Carter, both of whom lost re-election. More encouraging for Mr. Biden is the example of Ronald Reagan, who was just one-tenth of a point above where the current president is at this stage of his presidency, but came back to win a landslide re-election in 1984.

Whit Ayres, a Republican consultant, said it was telling that Mr. Biden was tied or behind “a former president carrying more baggage than a loaded 747” and warned Democrats against complacency.

“Democrats are in denial if they think Biden cannot lose to Trump in 2024,” he said. “Trump can most certainly win. Joe Biden is asking the country to elect a candidate who will be 82 years old, who has clearly lost a step, running with a vice president whom almost no one in either party thinks is ready for prime time.”

The Post-ABC poll and other surveys contain grim news for Republicans as well. While Mr. Trump leads or keeps relatively even with the president, he may have a ceiling beyond which he cannot rise, while Mr. Biden can still win over ambivalent independents who dislike the former president, analysts said.

“While the poll is not great news for Biden, it’s not great news for the Republicans either,” said Anna Greenberg, a Democratic pollster. “Only about a third say they are strong supporters for Biden, DeSantis and Trump. It feels more unsettled than anything else.”

She said that the real choice between Mr. Biden and Mr. Trump, should it come to that, would force ambivalent Democrats and independents to come off the fence. “I noticed more softness among Democrats, but I have no doubt that no matter what skepticism Democrats tell pollsters right now, they are going to vote for Joe Biden,” she said.

Stuart Stevens, who ran Mitt Romney’s campaign against Mr. Obama in 2012 and is a vocal critic of Mr. Trump, noted that the Republican establishment worries that the former president cannot win even though he leads in some polls. “We seem to be in this weird moment when Republican elite are panicked that Trump can’t beat Biden,” he said. “I think that’s because they know that Trump is deeply flawed.”

David Axelrod, the former Obama senior adviser who was on the other side of that race from Mr. Stevens, agreed with his assessment. “What Biden has that no one else does is a record of having beaten Trump, which weighs heavily in conversations among Democrats about the race,” Mr. Axelrod said. “He also has a record to run on and a party out of the mainstream on some important issues to run against, with a deeply flawed front-runner.”

“The worry for Democrats is that the re-elect is subject to a lot of variables Biden can’t entirely control — including his own health and aging process,” Mr. Axelrod added. “Any setback will exacerbate public concerns already apparent in the polls about his condition and ability to handle four more years.”