The 13 states and District of Columbia with majorities approving of Obama's job performance in the first half of 2012 is a slight increase from Obama's 2011 totals, as all 10 states with 50% or greater approval in 2011 remained at that level and were joined by Rhode Island, Washington state, and Minnesota. Additionally, Obama's approval rating fell just below the majority approval threshold in Michigan and Wisconsin, two key swing states this presidential election year. Six other states had approval ratings of 46% or 47%.

The 50% approval mark is significant because post-World War II incumbent presidents who have been above 50% job approval on Election Day were easily re-elected. 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.

From January to June of this year, Gallup asked more than 90,000 U.S. adults whether they approved or disapproved of the job Obama is doing as president. Nationwide, 46% of Americans approved and 46% disapproved during this time. Gallup interviewed at least 500 residents in 41 states and at least 1,000 residents in 32 states in the first half of the year. Gallup weights each state sample according to U.S. Census parameters to ensure it is demographically representative of that state's adult population.

Source: Gallup Poll | Jeffrey M. Jones