Dead Candidate Options

Answers to the question: What happens if a presidential candidate passes away at the last second?

Each party has its own protocol for this scenario, but in neither case does the running mate automatically take over the ticket.

If John McCain were to die before the election, the rules of the Republican Party authorize the Republican National Committee to fill the vacancy, either by reconvening a national convention or by having RNC state representatives vote. The new nominee must receive a majority vote to officially become the party candidate.

If Barack Obama were to die before the election, the Democratic Party's charter and bylaws state that responsibility for filling that vacancy would fall to the Democratic National Committee, but the rules do not specify how exactly the DNC would go about doing that. (Congress could also pass a special statute and push back Election Day, giving the dead candidate's party time to regroup.)

What if the president-elect dies after election day, but before inauguration day?

The 20th Amendment states that if the president-elect dies before beginning his term, then the vice president-elect assumes his or her spot. However, the point at which a candidate officially becomes "president-elect" is debatable.