If a candidate dies after receiving their party's nomination...

[Independents for George Santos]

Does their running mate automatically become the nominee in the same way that the vice president ascends to the presidency? What if that running mate is the current vice president, and hence becomes the president?

[Dr. MB]

The party would select a new nominee who would likely be the running mate.

[StateBoiler]

Republican National Committee Rule #9

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My personal opinion is this rule needs expounded on better.

There are 4 different timeframes that ultimately need to be considered:

-post-primaries/pre-Convention - Rule 9 above does not apply; however, a lot of delegates that RNC Rules say you're sworn to vote for a certain candidate suddenly don't have a candidate to vote for at the National Convention, and you're not going to redo the primaries; only example I can think of this happening is RFK in 1968, and Humphrey assumed all of his delegates in a controversial decision

-post-Convention/pre-election - this is what Rule 9 intends to address; with early voting though now occurring so early, you can't change the ballot once the first votes are cast; if it's in the month before an election, a dead candidate is going to be on ballots; this occurred in my county in the 2016 election where one of the candidates died 4 days prior to the election, and in the ensuing lawsuit (elect 3, all 3 Republicans won, 1 of them was deceased, Democrat that finished 4th said he should've taken the seat); the Election Board and the judge both said state law needs updated to account for this scenario https://www.theindianalawyer.com/articles/42760-judge-affirms-dead-candidate-winner-in-allen-county-election

-post-election/pre-Electoral College - this happened in 1872 with Horace Greeley and 1912 with James Sherman, who were both on losing tickets; the parties in both instance nominated replacements, although in Greeley's case the votes were split to several people; votes for deceased people are disqualified

-post-Electoral College/pre-inauguration - the parties here can do nothing; this is all handled by the 25th Amendment; the VP would either become president or the president would nominate his replacement VP; if both die, it goes to the Speaker of the House

[Gary J]

A practical difficulty might arise if a winning candidate was to die on the day the electors were due to cast the formal electoral votes. There would probably be no time for a new official nominee to be named.

Would Congress have to investigate if electoral votes for the deceased candidate had been cast before or after their death or before or after their death was known? Alternatively Congress could disregard the Greeley precedent and just count all votes for the deceased candidate (which might be the best solution, on the basis that someone who was alive at the start of the day of election should be regarded as available to receive votes all day precisely to avoid the confusion that might otherwise result).

If electoral votes for the deceased candidate were disregarded and this resulted in no candidate receiving a majority of electoral college votes, there would have to be a contingent election (election by House delegations amongst the top three candidates receiving valid electoral votes for President or election by Senators amongst the top two recipients of Vice Presidential electoral votes). That might lead to the party which "won" the Presidential election not having a candidate for the contingent election or having to elect someone who had only received one or two electoral votes from faithless electors (or the candidate who had been lucky enough to receive the highest number(s) of electoral votes if the majority party electors had heard of the original nominees death in time to splinter their votes between random prominent people).

[SteveRogers]

A practical difficulty might arise if a winning candidate was to die on the day the electors were due to cast the formal electoral votes. There would probably be no time for a new official nominee to be named.

Would Congress have to investigate if electoral votes for the deceased candidate had been cast before or after their death or before or after their death was known? Alternatively Congress could disregard the Greeley precedent and just count all votes for the deceased candidate (which might be the best solution, on the basis that someone who was alive at the start of the day of election should be regarded as available to receive votes all day precisely to avoid the confusion that might otherwise result).

If electoral votes for the deceased candidate were disregarded and this resulted in no candidate receiving a majority of electoral college votes, there would have to be a contingent election (election by House delegations amongst the top three candidates receiving valid electoral votes for President or election by Senators amongst the top two recipients of Vice Presidential electoral votes). That might lead to the party which "won" the Presidential election not having a candidate for the contingent election or having to elect someone who had only received one or two electoral votes from faithless electors (or the candidate who had been lucky enough to receive the highest number(s) of electoral votes if the majority party electors had heard of the original nominees death in time to splinter their votes between random prominent people).

The 20th Amendment does notably give congress the power to come up with rules to handle this scenario:

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But of course Congress has never passed any such law. Presumably if the situation arose, congress could pass emergency legislation allowing the electors who cast their votes for the deceased candidate to nominate someone else to take their place. But of course depending on which party controls congress, they might not be inclined to act in good faith if this situation arose, and we’d be left with a constitutional crisis.

[MASHED POTATOES. VOTE!]

There were two major party Vice Presidential candidates that were replaced between nomination and the election. After Vice President and Taft's running-mate John Sherman died in the last weeks of the campaign in 1912, the GOP designed Nicholas Murray Butler to receive all electoral votes that would normally go to Sherman (I presume it was too late for ballot changes).

The second instance would be McGovern dropping Eagleton in 1972. It feel to the DNC to confirm the replacement in person of Sargent Shriver (although it wasn't unanimous; I remember Wayne Morse receiving some votes).

I supposed it would be up to the party to pick a presidential replacement as well, as there's no "VP nominee automatically becomes Presidential nominee" mechanism, at least as far as I know.

[Torrain]

... then they likely chose an elderly candidate, which will lead to poor optics in the GE.

If Hillary had had a stroke in August of 2016, the only viable replacement palatable to both the activist and estalishment wings would have been Biden, (or Sanders if the delegates re-voted). Neither of which were spring chickens.