See Charlie's recent article on the economy and indications for the campaign. Lots has been said comparing Reagan's renaissance after his 1982 midterm drubbing to Obama now. Not saying Obama won't bounce back, but the comparison isn't necessarily so apt.
After unemployment peaked at 10.8 percent in time for the 1982 midterm election, strong economic growth in the latter half of 1983 and through 1984 dropped the unemployment rate down to 7.2 percent by the November 1984 election, allowing the president to run on the “Morning in America” theme and rack up a 49-state landslide.It is highly unlikely that unemployment will drop to 7.2 percent by November 2012. A decline to around 8 percent would likely bode well for Obama’s reelection chances. If it remains around 9 percent, one can argue that most any major Republican nominee has a good chance of winning. Under this argument, the tipping point is between 8 and 9 percent.Among 49 top economists surveyed this month by Blue Chip Economic Indicators, the consensus gross domestic product forecast was 3.2 percent for this year and 3.3 percent for next year, nowhere near the levels of growth that worked to benefit Reagan—4.5 percent in 1983 and 7.2 percent in 1984. The 10 most optimistic forecasts among the 49 projected an average GDP growth rate of 3.9 percent for 2012, while the pessimists were at 3.2 percent. ... Differences voters have with Obama over priorities and policies during his first two years in office would likely be exacerbated or perpetuated by weak GDP numbers and high unemployment rates.
Also see Stu's piece on Romney's outlook for POTUS 2012-- he argues Romney, while being a frontrunner, faces some daunting challenges.