Democratic leaders are in a bind. Biden remains popular with the party’s rank-and-file, who are less concerned about swing-state opinion polls, “electability” questions, or down-ballot considerations than are party insiders, who obsess over these matters. It nevertheless appears obvious to many observers that the president, whose legendary “gaffes” are beginning to look like unambiguous signs of dementia, will eventually have to come up with a dignified way to exit the race. But doing so ahead of his nomination poses significant problems for Democratic Party leadership. After all, the Democrats are fractious by nature—but even more so now. The party includes an extraordinarily broad spectrum of opinion. Some senior members believe that Israel is a pariah state; others are hawkish Zionists. The party includes socialists who seek to end private markets in housing and health care and fiscal centrists who voted against Biden’s economic agenda. The party has built this unlikely coalition on a foundation of minority identitarianism and “inclusion,” so representation at the level of race, ethnicity, gender, and sexual orientation is a central concern in forming consensus.

This factionalism is helpful as a means of attracting voters who feel disenfranchised, but much less so when it comes to facing something as contentious as an open convention, which is essentially the proposal being pushed by people calling for Biden to withdraw. An open convention, in which no candidate has secured a majority of votes ahead of time, hasn’t occurred in either party since 1952, when it took multiple ballots before Adlai Stevenson won the Democratic nomination.