Republican presidential candidate, former Massachusetts Gov. Mitt Romney and Sen. Charles Grassley, R-Iowa, wave before Romney spoke about the economy during a campaign stop at Kinzler Construction Services, Friday, Oct. 26, 2012, in Ames, Iowa. (AP Photo/Charlie Neibergall)

Photo by: Charlie Neibergall

Republican presidential candidate, former Massachusetts Gov. Mitt Romney and Sen. Charles Grassley, R-Iowa, wave before Romney spoke about the economy during a campaign stop at Kinzler Construction Services, Friday, Oct. 26, 2012, in Ames, Iowa. (AP Photo/Charlie Neibergall)