The electors don’t have to vote for McCain.
No the Electors do not. But after the vote is submitted to the Congress and Zero disqualified the choice would go to the House and be limited to the top 3 vote getters, in this case McCain, Mccain and MCcain. See the 12th and 20th amendment.
“The electors don’t have to vote for McCain.”
That depends on how SCOTUS rules (if they take the case) ...
If they rule the election null and void, they could order a new election (with certified candidates) - OYYY VEYYY !!!
But, if they rule that ONLY Obama’s eligibility is null and void, HE would be DQ’d AND HIS electors (the ones about to be certified) WOULD ALSO be DQ’d. AND, ALL popular votes for Obama would be DQ’d.
The election would then be counted as if Obama was NEVER on the ballot. McCain would then win the popular vote, HIS electors would be certified, and (presumably) they would vote for McCain.
Biden WOULD NOT get Obama’s popular votes or his electors for POTUS - since he WAS NOT on the ballot for POTUS. But, HE MIGHT get the VP slot - since he was qualified and was on the ballot for VP.
For that matter most of them don't have to vote for anyone, even the ones bound by statute, would never be held accountable, or the penalty is so minute as to not matter.