Winning Ohio's 18 electoral votes put President Barack Obama's race to re-election on cruise control.
Efforts by Mitt Romney's campaign in the final weeks to counter Obama's touting of the auto industry bailout appeared to have little impact. Pro-Romney ads in Ohio had belittled the president's approach, which Democrats credited with saving plants and many thousands of jobs in the state.
Exit polling of Ohio voters indicated wide support for the federal help that boosted Obama.
The president handily carried northern Ohio areas where much of the state's auto-making goes on as he narrowly captured Ohio for a second time. Romney became the latest Republican to lose Ohio, then lose the race.