Nate Cohn shakes his head:
The president performed better among white voters in the Columbus media market, but the auto bailout and attacks on Bain probably weren't responsible for the president’s strength in the state's best educated metropolitan area … Instead, historic black turnout carried Obama to victory in the Buckeye State. As mentioned prior to the election, much of Obama’s improvement over Kerry was attributable to gains among black voters. In 2004, African Americans represented 11 percent of the Ohio electorate and voted 84 percent for Kerry. In 2012, 15 percent of Ohio’s electorate was African American and voted 96 percent for the president.
The epicenter of the auto industry … is a place where Obama's support declined by an above-average amount. That doesn't prove anything regarding the bailout, of course, but it's certainly the opposite of what you would expect if it gave him a huge boost.