Obviously, the President also stands a greater chance of re-election if he has a Republican House of Representatives to run against. He'll get to be all Presidentially veto-ing all sorts of nonsense. I've been accused of being a Marxist, yet while Harpo's my favourite, it's Groucho I'm always quoting. Odd, that.
If the GOP controls the House they'll make the Clinton impeachment BS seem like a pillow fight. Obama will get to run against "the crazy." Plus the possibility of Palin running for Prez in 2012 will turn TPTB back towards sane, and controllable Dems.