Indiana U.S. Senate candidates Joe Donnelly (left), a Democrat, libertarian Andrew Horning (center) and Republican Richard Mourdock participate in a debate in New Albany, Ind., on Oct. 23, 2012. (Associated Press)

Photo by: Michael Conroy

Indiana U.S. Senate candidates Joe Donnelly (left), a Democrat, libertarian Andrew Horning (center) and Republican Richard Mourdock participate in a debate in New Albany, Ind., on Oct. 23, 2012. (Associated Press)