“The 50 percent approval mark is significant because post-World War II incumbent presidents who have been above 50 percent job approval on Election Day were easily re-elected,” write Gallup. “Presidents with approval ratings below 50% have more uncertain re-election prospects. Historically, two presidents below 50% in their final approval rating before the election — George W. Bush and Harry Truman — won, and three, Gerald Ford, Jimmy Carter, and George H.W. Bush, lost.”

The District of Columbia and the states in which Obama is at 50 percent or above have a combined 188 electoral votes — a solid beginning toward the 270 he needs for re-election. But a number of the states Obama will need to win — Ohio, at 44 percent, and Florida, Virginia, and Pennsylvania, all at 46 percent — are in the iffy mid-40s range.

Obama’s total of 13 states in positive job approval territory is actually a slight improvement from 2011, where he was above water in just ten states.