For those asking what happens if a person is incapacitated before, on, or after the election ...
"If something happened after the conventions but before the election, the national party committees would pick another nominee. Under Republican rules, the Republican National Committee could reconvene the national convention, although Pildes told me it’s hard to imagine that being feasible. So in both parties, national committee members would vote to elect a new nominee.2 Pence would once again be the obvious choice for Republicans, although the GOP would also have to pick a new vice presidential nominee (as would the Democrats if this situation arose for them). And while Democrats could try to back a former candidate or an outsider who didn’t run — say, New York Gov. Andrew Cuomo — Brown said a crisis like this would likely push the Democratic National Committee to put the vice presidential nominee at the top of the ticket. “I assume that the Democrats would attempt to follow that same pattern [as the GOP],” she said.
Neither party has ever had to replace someone at the top of the ticket, but Democrats do have some experience with replacing someone in the No. 2 spot. In 1972, the national convention nominated Missouri Sen. Thomas Eagleton to be George McGovern’s running mate, but after reports surfaced that Eagleton had received electroconvulsive therapy for depression, he withdrew, and the DNC chose Sargent Shriver to fill the vacancy. Brown cautioned me not to read too much into how this worked, though, because she argued that the process would work differently if someone died. “It’s different with a death because a death is unexpected,” said Brown. “Whereas by the time you get to Eagleton withdrawing at McGovern’s request, the whole party is kind of on board with that already.”
And what if something happens very close to Election Day? It’d probably be really hard to pick a replacement in time to update ballots, as most deadlines to certify state ballots would have passed by early October — not to mention other logistical hurdles that could pose problems, such as mailing ballots for overseas military service members in time, or making last-minute adjustments to absentee ballots. It’s entirely possible that if the candidate died only a few days before Nov. 3, voters might not know who the party’s nominee was when they go to the polls.
Again, neither party has experienced this at the top of the ticket, but Republicans did have this happen to a vice presidential candidate in 1912, when sitting Vice President James Sherman died on Oct. 30, just days before the election. This left insufficient time for the RNC to meet and nominate a replacement to join President William Howard Taft on the GOP ticket, but it was also largely a moot point as Taft lost to Woodrow Wilson. The RNC still chose a replacement, Nicholas Murray Butler, president of Columbia University, who received all eight of Sherman’s electoral votes, but it’s unclear whether a new presidential pick would receive the electoral votes intended for the original nominee today.
That’s because, unlike in 1912, more than half the states have laws that attempt to bind electors to a state’s vote. In fact, there’s an ongoing case in front of the Supreme Court about whether members of the Electoral College are free to vote for whomever they want or whether state laws can require them to vote a certain way. And depending on how the court rules, that could affect the ability of individual states to adjust for the unexpected death of a presidential nominee. For instance, Michigan’s law requires an elector to vote for the ticket named on the ballot whereas Florida’s rules say that an elector is to “vote for the candidates of the party that he or she was nominated to represent.”
Finally, if the nominee was incapacitated after Election Day, a lot might depend on whether he is considered the “president-elect.” If he is, it’s actually pretty straightforward — the 20th Amendment says the vice president-elect shall become president. But if it all happened before the Electoral College votes on Dec. 14 or even before Congress counts the electoral votes on Jan. 6, 2021, it’s not clear what would happen next, as he might not be considered the president-elect. There is one instance of this happening — in 1872, Horace Greeley died on Nov. 29, just before the Electoral College’s Dec. 4 gathering and most of his 66 electoral votes were split among four alternate candidates (including Greeley’s vice presidential nominee, Benjamin Gratz Brown), but this example is largely academic, too, as Greeley had already lost to Republican President Ulysses S. Grant."
From back in April.
https://fivethirtyeight.com/features...un-for-office/