Primaries do not start until next year. The political conventions are still a year away. The "real" presidential campaign traditionally starts the Labor Day weekend prior to the election. The further away the election is, the harder it is to predict. That said, what can we say about the next election based on prior ones?
First, President Obama's poll numbers may be down but they will rise closer to the election. Hundreds of millions of dollars of campaign spending does that and Obama is rumored to be planning on spending an even billion dollars on his reelection. That means that polls showing his disapproval rate as being unelectable are premature.
The polls do show some real problems for Obama. This far out, it is not unusual for him to poll below a generic candidate. It is the specific matches that mean something. Voters have a tendency to imagine the generic candidate as being perfect but, when faced with real people, pull away (Anyone but Obama... except that guy). Obama's problem is that he is polling around even with specific candidates. Worse, they are real candidates who have a shot at the nomination.
History tells us that Perry is a bigger threat to Obama than he is given credit for. Many dismiss him as being too far-right to be electable. In 1979 Reagan was dismissed the same way. Clinton was dismissed as being too flawed in 1991. Both went on to unseat incumbent presidents.
Obama's reelection hinges partly on the economy and partly on foreign affairs. He has a year for the economy to recover. If we are in a robust recovery a year from now then all will be forgiven. He will be the next Reagan. If we still have unemployment in the 8%-9% range and high inflation then he will be the next Carter. Given the economic problems in Europe, chances of a robust recovery are slim.
So far, Obama's mark on foreign affairs has been minimal. He continued many of Bush's policies, especially in Iraq and Gitmo. He managed to turn Afghanistan from the "good war" into a "bad war". Yes, Bin Laudin was executed during his watch but that is already old news. Ghaddafi's overthrow may be good news but the election will not hinge on it. In fact, it is hard to think of anything overseas that can help Obama but many things could drag him down.
So far, Obama has involved us in multiple foreign conflicts on various levels. All of these are conflicts of choice - the sort of thing that the Democrats are supposed to be against. This will hurt Obama's base. They may not vote Republican but they can sit the election out.
A successful terrorist attack would be a disaster for Obama. So would something like the Iranian Hostage Crisis.
None of this looks good for Obama. Instead of being the candidate of Hope and Change, he will be "the guy who got us into this mess". The plans that have leaked out of his campaign reflect this. Instead of running on his accomplishments, he hopes to pull the other side down. He will propose an ineffective jobs program that cannot pass Congress so that he can run against that. His campaign already started a whisper campaign against Romney because he's "weird" (i.e. Mormon).