Republican presidential candidates Santorum, Romney and Gingrich are seen on a TV monitor as they participate in a candidates debate in Charleston

Republican presidential candidates (L-R) former U.S. Senator Rick Santorum (R-PA), former Massachusetts Governor Mitt Romney and former House Speaker Newt Gingrich are seen on a TV monitor as they participate in a Republican presidential candidates debate in Charleston, South Carolina, January 19, 2012. REUTERS/Jason Reed