To be honest, I don't care how beatable Sarah Palin might be in 2012. I know some liberals hope the GOP nominates someone totally crazy (and therefore, presumably, unelectable), and I sometimes relish the thought of them shooting themselves in the foot again by putting up the national equivalent of Sharron Angle or Christine O'Donnell against Obama. The problem with that is, the crazier they get, the less rational our entire political system gets. You may have noticed that the GOP did not learn anything from 2008 - in fact, they learned entirely the wrong thing. The way the party is now, George W. Bush might not be acceptable to them in 2012!
Not that there's anyone currently being talked about as a GOP candidate who isn't basically nuts, but I really wish there were. Sure, if they nominated an actually sane person that might diminish Obama's chances, but at least it might start the certain to be long and difficult process of rebuilding the GOP as an actually sane political party instead of a collection of ignorant zanies and cynical exploiters. Winning isn't everything - as some once-respectable Vietnam vet once wrote, "Country first."
Obama can fight just as well against the equivalent of Arnie Vinick as he can against Sarah Palin. He can hold his own against a tough but rational conservative. He doesn't need a lunatic opponent to win - and neither do we. Sure, it just makes his re-election that much more likely (although if unemployment is down next year he'll probably win no matter who gets the GOP nod), but it also makes the continuing derangement of our political discourse equally much more likely.
And, in the long run, that's a terrible thing for our country. We need to encourage the GOP to step back towards reality, not keep running away from it as fast as they can. And every crazy who the GOP nominates takes them a step further away, not closer. It moves the discourse itself that much further away from reality, making it tougher in the long run for anyone to maintain a civil, sane debate.
Okay, that doesn't seem to be on the menu, not anytime soon. And, given that the GOP seems determined to fully embrace the crazy (and there's nothing we can do to stop them), it can fairly be argued that we might as well try to use their insanity to our maximum advantage. But we don't have to like it - and we especially don't have to wish for it.