Romney, in turn, has sharply criticized Obama's support for stricter regulations on coal and natural gas. It's seen as a way in with white working-class voters, on which his candidacy depends. "Stop the War on Coal. Fire Obama," read signs that dot the countryside of areas where Romney has held multiple events.
White blue-collar workers prefer Romney to Obama, but less so than they did Republican George W. Bush, who carried Ohio in 2004. These voters are considered still persuadable, although Romney may have hurt himself with his comment that the 47 percent of Americans who pay no income tax believe they are victims entitled to government help.
Romney's position on the auto bailout also dogs him in a state that's heavily reliant on the industry. Obama's decision to offer government support to automakers meant protection for thousands of jobs at parts and supply companies in Ohio.
Romney wrote a 2008 op-ed headlined "Let Detroit Go Bankrupt," which has become a rallying cry for Democrats. They have argued Obama's support for the bailout has had a hand in Ohio's drop in unemployment, which is now lower than the national average.
In the final weeks, both campaigns insist they have the edge in the critical ground game. That battle was playing out in the courts, as well, with Ohio's election chief saying Tuesday he will appeal a ruling that reinstates the final three early voting days in the state.
Ohio Secretary of State Jon Husted called a decision last week by a federal appeals court "an unprecedented intrusion" into how states run elections.
Husted said Friday's decision by the 6th U.S. Circuit Court of Appeals would affect how elections are run in all 50 states. The appeals court in Cincinnati affirmed a lower court ruling and returned discretion to set hours on the final three days to local boards of elections.
Kasie Hunt reported from Washington. Associated Press writers Steve Peoples in Ohio, Thomas Beaumont in Iowa and Philip Elliott and Julie Pace in Washington contributed to this report.
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