Republican presidential candidate and former Massachusetts Gov. Mitt Romney greets supporters as he campaigns at the3Iowa Events Center, in Des Moines, Sunday, Nov. 4, 2012. (AP Photo/C

 

              Republican presidential candidate and former Massachusetts Gov. Mitt Romney greets supporters as he campaigns at the3Iowa Events Center, in Des Moines, Sunday, Nov. 4, 2012. (AP Photo/C
Republican presidential candidate and former Massachusetts Gov. Mitt Romney greets supporters as he campaigns at the3Iowa Events Center, in Des Moines, Sunday, Nov. 4, 2012. (AP Photo/Charles Dharapak)