He added, "You can't make it happen if you write off half the nation before you take office."
Obama supporters are also working to keep Romney's "47 percent" comments alive. Democratic super PAC Priorities USA Action and a political group tied to the American Federation of State, County and Municipal Employees released a radio ad in Ohio and Virginia airing the remarks. The ad, part of a $1.25 million radio buy, tells listeners Romney's "just not looking out for us."
Obama flubbed a line at Kent State while building to his argument for keeping jobs in the United States. He mistakenly said, "I want to see us export more jobs." He quickly corrected himself, saying he meant to say "export more products."
"Excuse me," Obama said. "I was a channeling my opponent there for a second."
Associated Press writers Kasie Hunt and Steve Peoples in Ohio, Beth Fouhy in New York and Ben Feller and Jim Kuhnhenn in Washington contributed to this report.
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