Do you think a billionaire could buy the presidential election?

I think for something like this Congress could ram through impeachment between 1/3 and 1/20.

Yes, of course, I forgot about impeachment. But are you sure that they really can do it before the president-elect assumes office, or if they’d have to do it just after his inauguration?

Also, I assume our crook would also have bribed the electors to elect his chosen vice-presidential candidate; can Congress impeach them both simultaneously? (I suppose so.)

Yes, that’s also quite likely.

Article II, Section 4 of the Constitution states:

*The President, Vice President and all civil Officers of the United States, shall be removed from Office on Impeachment for, and Conviction of, Treason, Bribery, or other high Crimes and Misdemeanors. *

Until he’s sworn in, the President-elect is not the President, so I don’t see how he can be preemptively impeached.