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Republican presidential candidate Mitt Romney pins for sale fill a poster board outside of Carter Machinery Company in Salem, Va. on Tuesday, June 26, 2012 during a Romney event at the company. (AP Photo/The Roanoke Times, Kyle Green)

Associated Press
Republican presidential candidate Mitt Romney pins for sale fill a poster board outside of Carter Machinery Company in Salem, Va.  on Tuesday, June 26, 2012 during a Romney event at the company. (AP Photo/The Roanoke Times, Kyle Green)
Republican presidential candidate Mitt Romney pins for sale fill a poster board outside of Carter Machinery Company in Salem, Va. on Tuesday, June 26, 2012 during a Romney event at the company. (AP Photo/The Roanoke Times, Kyle Green)