Millions of things could happen. The biggest being, of course, the economy. What happens in Europe economically may indirectly determine a U.S. presidential election. That's just one (maybe two or three depending on how you look at it). Who thought a year before Obama was elected, he would be?
I'm not saying I dislike Obama, if that's what you're thinking- just that the future is not certain. Being too intuitive can be dangerous.
Santorum is looking up in the polls, btw. He might take Iowa. You might have to add him to the list Blue.