What happens if a presidential candidate dies or has to leave the race?

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While the 2024 presidential race seems set in stone as a rematch between President Joe Biden and former President Donald Trump, it’s also true that things happen.

Back in November 1872, for instance, the newspaper publisher and Democratic presidential candidate Horace Greeley died after Election Day but before the casting of Electoral College votes. While it did not affect the outcome – President Ulysses S. Grant easily won reelection – Greeley’s death created the difficult question of what to do with the 66 Electoral College votes he had won.

Most electors, meeting in state capitols, did not cast votes for the deceased Greeley, but rather split them among four other candidates. Congress did not count the three votes that were cast for a dead man.

In the more than 150 years since Greeley’s death, there have been two constitutional amendments related to presidential succession, but there is still some gray area when it comes to an unforeseen event that strikes a presidential nominee or candidate.

Today, polling suggests voters are worried that both Trump and Biden are too old for the job. Trump will be 78 on Election Day in November, and Biden will turn 82 later that month. Without being macabre, it’s worth knowing what would happen if, for whatever reason, either man was unable to continue with the race.

Replacing either man on the ballot – not that anyone is seriously talking about it – would be a messy and chaotic process that would uncover divisions and disagreements within the political parties. No one knows for sure what would happen if a candidate died or for some reason needed to withdraw from the race.