You're talking primarily presidential politics, but I think the House and the Senate are going to play a bigger role this year.  If both of these go heavily Democratic a McCain presidency will be completely ineffective unless he compromises on virtually everything.  I'm of the opinion that this wouldn't necessarily be a bad fit, since I don't like a single party controlling all of the government.  So my dirty little secret is that I don't much care if McCain wins or loses as long as his party loses the other two branches of government entirely.

I think anyone else but McCain on the Republican side would have resulted in a deadlocked government under those circumstances.  I still worry that if McCain were to win he would allow incompetents and party loyalists to continue to remain at the head of the important agencies.  This is among the worst aspect of the Bush/Cheney lame-ass administration.