The People’s Choice is by Jeff Greenfield, and it’s a little obscure, I guess. Written in 1996, it’s a satirical novel about a real oddball situation where the President-elect of the USA dies between the election and the convening of the Electoral College, thus producing an unique situation in American politics. I know, I know: real unlikely stuff, here. The country would have to be in the middle of an amazing string of low-probability events, most of them bad, before that could even seem remotely plausible.
Still: improbable or not, so far it’s holding my interest.