For months now, discussions about 2024 have mostly focused on whether Donald Trump will run for president. This framing works out well for both Trump and the political media: Trump gets the spotlight he craves, and the political media gets the clicks and eyeballs they need. 

But, the far more exciting and consequential question is whether or not Pres. Joe Biden will be on the ballot in 2024. Democratic voters are at best lukewarm at the prospect of a Biden reelection campaign. That sentiment has been picked up in both quantitative and qualitative surveys. A March Wall Street Journal survey found a majority of Americans (52 percent) don't think Biden will run in 2024, including 32 percent of Democrats; another 26 percent of Democrats were unsure if he should run for re-election. A recent poll by Echelon Insights found just 51 percent of Democrats wanted to see Biden run in 2024. That Echelon poll mirrors AP/NORC and CNN surveys taken earlier this year that found just under half of Democrats wanted to see Biden on the ticket again. Focus groups pick up this hesitancy as well, with many Democratic and Democratic-leaning voters questioning Biden’s strength of leadership. 

It is very, very rare for a sitting president not to seek reelection. Most of the men who've held the post have aspired for years — if not a lifetime — to get the job. This is especially true for this president, who has run for the job three times. It's also much easier for the opposition party to win an open seat than to defeat a sitting incumbent, which is one big reason Democratic insiders and elites are anxious about a Biden-less ticket in 2024. 

Few of us still actively involved in politics — either on the campaign side or the reporting side — have witnessed an incumbent president decline to run for reelection. It was more than 50 years ago when President Lyndon Baines Johnson announced on March 31, 1968 that he would "not seek, and I will not accept, the nomination of my party for another term as your president." By that point, Johnson was already facing a serious primary challenge from Sen. Eugene McCarthy (whom Johnson narrowly defeated in the New Hampshire primary), and the field of challengers had recently expanded to include Sen. Robert Kennedy. His job approval rating in mid-March of 1968 was a dismal 36 percent, including an anemic 52 percent rating among Democrats. 

Like the other two presidents who chose not to seek reelection in the last 100 years (Calvin Coolidge and Harry Truman), Johnson was a former Vice President who had come to office because of a sitting president's death. The last president not to seek reelection and who didn't ascend to the office via the sitting president's death was Pres. James Buchanan in 1860. In other words, it's been more than 160 years since a president who first ascended to the office in an election, not because of the death of a sitting president, decided not to run for another term. 

It's also been more than 30 years since we've seen a sitting president face a serious primary challenge. Pat Buchanan never won a primary in 1992, but he proved to be a more serious threat to Pres. George H.W. Bush than many had expected. It's been more than 40 years since the sitting president came close to losing the party nomination. Pres. Gerald Ford narrowly held off former California Gov. Ronald Reagan in 1976, thanks in part to last-minute maneuvers at the GOP convention. Pres. Jimmy Carter's margin over Democratic Sen. Ted Kennedy in the 1980 Democratic primary was larger than Ford's, but Kennedy didn't concede until the August convention. In each case, the incumbent president lost his reelection. 

Historically speaking, it's much riskier for Democrats to replace — or try to replace — Biden in 2024. But, of course, we've also never had a president seek reelection at the age of 82. For some perspective, LBJ was just 61 years old when he left office in 1968. 

Given we haven't seen either one of these scenarios — a president retiring after one term or getting a serious primary challenge — in many, many years, it's hard for us to imagine how this would work. Would the party apparatus rally around the incumbent or let the chips fall where they may? Would Biden announce his intentions on whether he'll seek a second term early enough to give his potential successors or challengers enough time to prepare? If he decides to forgo reelection, how early will he be willing to declare himself a lame-duck? The longer he waits, the messier the Democratic nomination fight. Will a Democrat jump into the race regardless of Biden's intentions?

And then there's the 800-lb gorilla in the room: Vice President Harris. It's no secret that many in the political establishment see her as a weak 2024 nominee. She also lacks grassroots strength outside of DC for a potential candidacy. But, while the vice president has traditionally been the obvious successor in a case like this, that doesn't mean it will happen. But, say many Democrats I speak with, if not Harris, than whom? And, who on the Democratic bench can beat Trump in 2024? I don't know. And, guess what, no one else does either. 

The dirty little secret about early presidential candidate assessments is that they are usually wrong. Candidates that look great on paper (Tim Pawlenty, Scott Walker, Kamala Harris) often fail to live up to the hype. Candidates who are dismissed as long-shots, or gadflies (Pete Buttigieg, Bernie Sanders, Rick Santorum), often over-perform expectations. 

The best candidates are the ones that meet the moment. Joe Biden was not the right candidate in 2008 when Democrats were looking for a change agent. He was the perfect candidate in 2020 when Democratic voters were desperate for someone whose only criteria was the ability to beat Donald Trump. 

However, an even more consequential concern for Democrats in 2024 is the state of the economy. As my colleague Charlie Cook wrote recently, there are signs for a downturn or recession within the next two years. In a recent Meet the Press appearance, noted inflation spotter and former Treasury Secretary Larry Summers told NBC's Chuck Todd, "The painful fact, though, is that historically when we've had inflation above 4 percent and we've had unemployment below 4 percent, essentially always, since World War II, that's been followed by a recession within the next two years."

Consciously or not, many voters, including many Democrats, voted for Biden in 2020, assuming that he would be a one-term president. They weren't thinking about the logistical and political difficulties that a one-term presidency would pose to the party in four years. Their top issue was beating Trump, and they saw him as the best choice to do that. At this point, however, Democrats are ready for someone new, and Democratic elites should dismiss these concerns at their own peril.

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