I'd say 35,000 illegal regristrations in one state alone by a nationwide lib organization helped them out, too.
One surprise this time was the high number of younger voters who turned out. I think it was 10 million more than 2004. Most of those votes are liberal, because they are still in college or just out, or they are in lower-paying jobs where the class warfare spiel gets some traction. They are also easily manipulated by the media (especially Hollywood and music).