President Barack Obama speaks during a campaign stop in Ames, Iowa, Tuesday, Aug. 28, 2012. The president's event in Ames, home of Iowa State University, is part of a tour through college towns. (AP Photo/Nati Harnik)

Photo by: Nati Harnik

President Barack Obama speaks during a campaign stop in Ames, Iowa, Tuesday, Aug. 28, 2012. The president's event in Ames, home of Iowa State University, is part of a tour through college towns. (AP Photo/Nati Harnik)