Republican presidential candidates (L-R) former U.S. Senator Rick Santorum (R-PA), Texas Gov. Rick Perry, former Massachusetts Gov. Mitt Romney, former Speaker of the House Newt Gingrich, U.S. Rep. Ron Paul (R-TX), U.S. Rep. Michele Bachmann (R-MN), and former Utah Governor Jon Huntsman Jr. are introduced for the Fox News Channel debate at the Sioux City Convention Center on December 15, 2011 in Sioux City, Iowa. The GOP contenders are in the final stretch of campaigning in Iowa where the January 3rd caucus is the first test the candidates must face before becoming the Republican presidential nominee.