What percentage of voters who voted for Bush in 2004 and Obama in 2008 will vote for Obama in 2012 do you think? Just asking. I actually know someone who did that. 
I'm curious what % of voters who voted in both elections did that and what their party affiliation is. As you probably have seen elsewhere, the number of actual swing voters is smaller than advertised. 2/3 of "Independents" are actually partisans. But between actual Indy swingers and soft partisans who can stray, I don't think the voters in play are all that much, but not insignificant either.
As for liberal turnout for Obama, I bet the state of the economy will affect it more than Obama's centrism.
