With the 2024 presidential election four months away, Democrats are facing a perfect political storm. President Joe Biden’s startlingly unfocused debate performance against Donald Trump has left party officials, major donors, and many of the Democrats’ likeliest voters calling for a change at the top of the ticket.

A few weeks ago, backing Biden was thought to be the Democrats’ best hope. After all, it’s not easy to beat an incumbent. Since 1932, only Herbert Hoover, Jimmy Carter, the elder George Bush, and Trump have failed to win re-election. Scenarios in which Biden would retire or face a credible primary challenge seemed needlessly dangerous. When the Democrats Harry Truman and Lyndon Johnson chose not to seek re-election – in 1952 and 1968, respectively – the Republicans Dwight Eisenhower and Richard Nixon rode to victory. Similarly, a Democratic primary challenge from Edward Kennedy in 1980 helped cripple Carter’s re-election campaign, ultimately sending Ronald Reagan to the White House.

With this history in mind, most Democrats thought it safer to stick with Biden, a man who has already beaten Trump once. No Democrat who aspires to be president someday wants to be the one to hobble an already vulnerable incumbent.

But growing worries about Biden’s age – he is 81 now and would be 86 at the end of a second term – have become the central issue of the campaign, even as Trump faces sentencing for a felony conviction in New York. (How’s that for an indicator of just how dysfunctional America’s politics have become?) Following Biden’s debate debacle, the editorial board of the New York Times, the center-left establishment paper of record, urged the president to drop out, and recent polls signal that about half of Democratic Party voters agree.

Unless Biden decides to leave the race, however, the odds of replacing him are virtually zero. During his sweep through the primary election season, he secured the support of the delegates he needs to be nominated at the party’s convention in Chicago in August. These delegates are pledged to back Biden unless he releases them. Moreover, even if the Democrats could easily replace Biden, who would be the party’s new nominee? Poll after poll shows that Vice President Kamala Harris is no more popular than Biden, but pushing her aside for another contender risks alienating large numbers of women and minority voters.

As for the alternatives – California Governor Gavin Newsom, Michigan Governor Gretchen Whitmer, Transportation Secretary Pete Buttigieg, and others – they are largely untested on the national stage. To understand how quickly an unproven candidate might flounder, look no further than Florida Governor Ron DeSantis’s hotly anticipated, but disastrous, attempt to take down Trump in this year’s Republican primaries.

Biden has so far shown no indication that he plans to step aside, and public shows of support from former Presidents Barack Obama and Bill Clinton are meant to confirm that the party is moving forward. The rationale for remaining in the race is that the president can still beat Trump. In America’s hyper-polarized political environment, millions of people who tell pollsters that Biden is too old to serve a second term will still vote for him, if only to keep Trump out of the White House. With both sides believing that the future of American democracy is at stake, voter turnout will likely be high across the board.

But the hill that Biden must climb will become steeper in the coming weeks as a steady stream of anonymous Democratic officials warn in the media that he must go. This drip-feed of negative coverage will weigh on the president’s ability to turn the page, at least until the convention next month. If there is any talk of advancing the date on which Biden is formally nominated, it will fuel speculation that he is panicking, even if he isn’t. And all this will be happening at a time when the Biden campaign hoped to keep media attention on Trump’s many liabilities.

For now, the Democratic Party is paralyzed. Ousting a sitting president would be an enormous political gamble; sticking with a stumbling incumbent might be even riskier. Trump, meanwhile, has enjoyed a charmed few weeks of good news. Almost all his legal headaches have been postponed until after the election. Sentencing has been delayed in his New York “hush money” trial. Recent Supreme Court rulings have reduced the likelihood of him facing jail time, as well as reminded conservative voters that he pulled the court rightward and would do so again if he wins. The media is more focused now on Trump’s search for a running mate than on his own erratic behavior.

The decision on Biden’s political future rests with the president himself, and it is impossible to know what he will do. For now, he appears intent on staying the course and trying to change the subject. But with each passing day, the pressure for a change at the top of the Democratic Party’s presidential campaign will grow. It is an unprecedented predicament in what was already a uniquely dysfunctional US presidential election.

Ian Bremmer, Founder and President of Eurasia Group and GZERO Media, is a member of the Executive Committee of the UN High-level Advisory Body on Artificial Intelligence.

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