Former U.S. Sen. Rick Santorum greets voters this summer in Iowa. The Republican presidential hopeful has spent most of his professional life in politics. Chip Somodevilla/Getty Images hide caption

itoggle caption Chip Somodevilla/Getty Images

Delaware County District Attorney Patrick Meehan (from left) and Gail Willard (mother of slain athlete Aimee Willard) accompany Sen. Rick Santorum as he introduces "Aimee's Law" along with Republican Arizona Rep. Matt Salmon at the county courthouse in Media, Pa., in 1999. The bill encourages states to keep murderers and sexual predators behind bars. William Thomas Cain/AP hide caption

itoggle caption William Thomas Cain/AP