There are some state laws that say such, but this has never been tested. Say the "president" chosen in November rapes and murders a nun before the election in December. You telling me that the electors chosen can't vote for anyone else?
Nonsense. Electors are entirely free to vote as they see fit.
Even if that did happen, the House of Reps would pick the POTUS. There is only one ballot in the Electoral College.