Much has been made of President Obama’s 50% job-approval rating, but that number in and of itself is “not particularly newsworthy,” writes Nate Silver for FiveThirtyEight.com. Obama could probably win in 2012 even with approval below 50%: George W. Bush was re-elected with the approval of less than half of the electorate, as did Harry Truman.
Silver’s analysis of recent elections suggests that a president at 50% approval is as much as 90% likely to win re-election. The chances of staying in office don't reach the break-even point until he slips to 44% approval. For the 2010 House elections, Obama’s current approval correlates to a loss of 26 seats, which, though it would sting, would see Democrats remain the majority party.