Good point. Look, 20% of US Voters say they are Liberal, about 40% say they’re Conservative. That leaves about 40% that are Independent, Green, Libertarian, Nazis and whatever-the-hell-else. It’s pretty simple math - you can’t win the Presidency unless you attract those in the middle who are not ideologues. Obama convinced the independents he was the better choice, although he’s beat feet hard to the left ever since - and guess what? He’s lost ‘em, and won’t get ‘em back.
All Sarah Palin (or anyone else) has to do is deliver a strong conservative message that is palatable enough to a sufficient number of Independents to win. Simply being “not-Obama” won’t be enough to win, but by 2012, it’s sure going to help as more Obama voters come to the realization they might have been fooled once, but never again.
Of that 40% who aren’t Conservative or Liberal, I think Palin should be able to get 10% +1 easily. Based simply on the fact that she’d be the First Woman President.