DANVILLE, KY – OCTOBER 11: U.S. Vice President Joe Biden (L) and Republican vice presidential candidate U.S. Rep. Paul Ryan (R-WI) (C) participate in the vice presidential debate as moderator Martha Raddatz looks on at Centre College October 11, 2012 in Danville, Kentucky. This is the second of four debates during the presidential election season and the only debate between the vice presidential candidates before the closely-contested election November 6. (Photo by Justin Sullivan/Getty Images)