Republican presidential candidate and former Massachusetts Gov. Mitt Romney is seen in silhouette as he boards his campaign charter plane while the sun sets in Cleveland, Ohio, Friday, Sept. 14, 2012, after holding a campaign rally and fundraising events. (AP Photo/Charles Dharapak)

Photo by: Charles Dharapak

Republican presidential candidate and former Massachusetts Gov. Mitt Romney is seen in silhouette as he boards his campaign charter plane while the sun sets in Cleveland, Ohio, Friday, Sept. 14, 2012, after holding a campaign rally and fundraising events. (AP Photo/Charles Dharapak)