President Barack Obama and Republican presidential nominee Mitt Romney greet moderator Bob Schieffer at the start of the third presidential debate at Lynn University, Monday, Oct. 22, 2012, in Boca Raton, Fla. (AP Photo/Pool-Michael Reynolds)

Photo by: Michael Reynolds

President Barack Obama and Republican presidential nominee Mitt Romney greet moderator Bob Schieffer at the start of the third presidential debate at Lynn University, Monday, Oct. 22, 2012, in Boca Raton, Fla. (AP Photo/Pool-Michael Reynolds)