Before his speech, and in front of TV cameras and photographers, Obama sat down with five Iowa students to hear about their career dreams and debt burdens.
While young voters were solidly behind Obama in the 2008 election, they are being aggressively wooed by Romney. His campaign is hoping he can appeal to young voters burdened by a bleak employment picture and student loan debt.
Obama's full entry into the campaign comes about six weeks later than when his predecessor headlined his first re-election rallies. But by the time George W. Bush headlined his first rally in Florida on March 20, 2004, his Democratic opponent, Sen. John Kerry, D-Mass., was already his party's nominee.
Associated Press writers Ben Feller and Ryan Foley in Iowa City, Iowa, and Philip Elliott in Washington contributed to this report.
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