President Obama and Republican presidential candidate Mitt Romney participate in the second presidential debate, at Hofstra University in Hempstead, N.Y., on Tuesday, Oct. 16, 2012. (AP Photo/Charles Dharapak)
Republican presidential nominee Mitt Romney and President Barack Obama spar over energy policy during the second presidential debate. (AP Photo/Charlie Neibergall)
President Barack Obama and Republican presidential candidate and former Massachusetts Gov. Mitt Romney participate in the second presidential debate. (AP Photo/Charles Dharapak)
Republican presidential nominee Mitt Romney answers a question as President Barack Obama listens during the second presidential debate. (AP Photo/Charlie Neibergall)
A member of the audience asks President Barack Obama a question during the second presidential debate with Republican presidential nominee Mitt Romney. (AP Photo/Pool-Win McNamee)
President Barack Obama, left, listens as Republican presidential candidate former Massachusetts Gov. Mitt Romney answers a question from a member of the audience. (AP Photo/Mary Altaffer)
Republican presidential nominee Mitt Romney, left, heads back to his seat after speaking during the second presidential debate with President Barack Obama. (AP Photo/Pool-Win McNamee)
President Barack Obama, foreground, and Republican presidential nominee Mitt Romney participate in the second presidential debate. (AP Photo/Mary Altaffer)
A member of the audience asks Republican presidential nominee Mitt Romney a question during the second presidential debate with President Barack Obama at Hofstra University. (AP Photo/Pool-Win McNamee)
President Barack Obama and Republican presidential candidate, former Massachusetts Gov. Mitt Romney, greet each other as they arrive for the second presidential debate. (AP Photo/Carolyn Kaster)
Moderator Candy Crowley, center, applauds as President Barack Obama, right, shakes hands with Republican presidential nominee Mitt Romney during the second presidential debate. (AP Photo/Pool-Michael Reynolds)
President Barack Obama, left, and Republican presidential nominee Mitt Romney speak to members of the audience during the second presidential debate. (AP Photo/Pool-Shannon Stapleton)
President Barack Obama, left, and Republican presidential nominee Mitt Romney confront each other during the second presidential debate at Hofstra University, Tuesday, Oct. 16, 2012, in Hempstead, N.Y. (AP Photo/Pool-Win McNamee)