If he really won OH with money-bombs against the conservatives Great White Hope, without even personally campaigning there, that ought to tell you he can compete if he DOES personally campaign there. Latest polls I have seen have him running a couple points ahead of Obama nationally as it is. Looking at the Electoral math, I would go hard in VA and OH if I were Obama, hoping that holding those states will offset the loss of FL. Last time, he won the first two by three (in VA) and two (in OH) times as much as he did FL (where he only won by 2% near the peak of his popularity.) If Romney does as Isaac suggested and puts Rubio on the ticket, FL is nearly hopeless, along with the Southwest, probably excepting NM. At that point, with NH partial to New Engladers it becomes very difficult for Obama to reach 270.

So, yeah, Romney has a very good shot at beating Obama; as Tom has noted, another major hit on the economy and/or foreign policy could sink Obama.