A lot of it depends on timing.

There’s a really good fictional take from before Bush/Gore, called “The People’s Choice” by Jeff Greenfield of all people.

https://en.m.wikipedia.org/wiki/The_People's_Choice_(novel)

Candidate wins the election, but dies before the electoral college votes.

So… the VP guy wins? Yeah, no. He wasn’t the candidate and can’t assume the role of President because he was never affirmed as Vice President.

So… the other candidate wins? Yeah, no. They didn’t get enough electoral college votes to be President.

So it all comes down to faithful and faithless electors.