Republican presidential candidate, former Massachusetts Gov. Mitt Romney pauses while addressing supporters at his campaign stop in Charlotte, N.C., Wednesday, April 18, 2012. (AP Photo/Jae C. Hong)

Photo by: Jae C. Hong

Republican presidential candidate, former Massachusetts Gov. Mitt Romney pauses while addressing supporters at his campaign stop in Charlotte, N.C., Wednesday, April 18, 2012. (AP Photo/Jae C. Hong)