Predicting the economy and Obama's reelection chances

Yale economist Ray Fair thinks the president is in good shape, based on his belief that the economy will be back in business when Obama starts campaigning. On paper, that makes sense (the economy trumps most everything else, all else being equal), but elections aren't usually won or lost on paper. From FiveThirtyEight's Nate Silver:

It is hard to imagine Mr. Obama failing to be re-elected if the economy is humming along at a 5 percent growth rate by this time next year, and 600,000 jobs are being created every month. Likewise, if unemployment is still at 10 percent or if there is a second period of recession brought on by, for instance, the European debt crisis -- something extraordinarily might have to occur for him to win a second term. But there is a lot of middle ground, and here's where models like these might not be much help.