Greybeards around Washington will tell you that one of the key turning points in the plunge toward extreme partisan bitterness in the House of Representatives came over the "Fighting Eighth" (I think that is the right district) in Indiana in the 1984 or 1986 election (I forget which exactly). If memory serves, the Democratic candidate won on election day by something like 20 votes. Then, after a recount found the Republican had won by an equally slim margin and was certified as the winner by the Indiana Secretary of State, House Democrats in Washington voted to refuse to seat the Republican, and seated the Democrat instead. House Republicans, especially Newt Gingrich, cried foul, and ratcheted up their guerrilla tactics in the House. (I probably have a number of details a bit off--I am going from memory.)
Before the 2004 election there were lots of stories in the media about whether there might be repeat of Florida 2000, and there were lots of preparations by both sides to litigate the matter, especially in Ohio. But so far there has been little or no talk about the prospects for this kind of disaster in this election. With control of the House and Senate possibly to be decided by just a seat or two, and with several House and Senate elections looking to be razor-close, there is a non-trivial probability that we could have several Florida-style post-election recount contests to decide control of the House or Senate or both.
This would not be a good thing.