Behind the Scenes of Round 2 of the Presidential Debates -- PICTURES

President Barack Obama and Republican presidential candidate and former Massachusetts Gov. Mitt Romney participate in the second presidential debate at Hofstra University in Hempstead, N.Y., Tuesday, Oct. 16, 2012.  ((AP Photo/Charles Dharapak))

Republican presidential nominee Mitt Romney, left, addresses President Barack Obama during the second presidential debate at Hofstra University, Tuesday, Oct. 16, 2012, in Hempstead, N.Y. ((AP Photo/Pool-Shannon Stapleton))

Republican presidential nominee Mitt Romney and President Barack Obama spar over energy policy during the second presidential debate at Hofstra University, Tuesday, Oct. 16, 2012, in Hempstead, N.Y.  ((AP Photo/Charlie Neibergall))

Republican presidential nominee Mitt Romney answers a question as President Barack Obama listens during the second presidential debate at Hofstra University, Tuesday, Oct. 16, 2012, in Hempstead, N.Y.  ((AP Photo/Charlie Neibergall))

President Barack Obama answers a question as Republican presidential nominee Mitt Romney listens during the second presidential debate at Hofstra University, Tuesday, Oct. 16, 2012, in Hempstead, N.Y.  ((AP Photo/Pool-Rick Wilking))

First lady Michelle Obama applauds before the start of the second presidential debate between President Barack Obama and Republican presidential nominee Mitt Romney at Hofstra University, Tuesday, Oct. 16, 2012, in Hempstead, N.Y. Seated right of Mrs. Obama is Seth Bodnar from Western Pennsylvania.  ((AP Photo/Pool-Michael Reynolds))

Ann Romney, wife of Republican presidential nominee Mitt Romney, waves while being introduced before the second presidential debate between President Barack Obama and Republican presidential nominee Mitt Romney at Hofstra University, Tuesday, Oct. 16, 2012, in Hempstead, N.Y.  ((AP Photo/Pool-Win McNamee))

Moderator Candy Crowley, center, applauds as President Barack Obama, right, shakes hands with Republican presidential nominee Mitt Romney during the second presidential debate at Hofstra University, Tuesday, Oct. 16, 2012, in Hempstead, N.Y.  ((AP Photo/Pool-Michael Reynolds))

Moderator Candy Crowley is introduced before the second presidential debate at Hofstra University, Tuesday, Oct. 16, 2012, in Hempstead, N.Y.  ((AP Photo/Charlie Neibergall))

Students stand near a display on the campus of Hofstra University in Hempstead, N.Y., hours before Tuesday's presidential debate. (AP Photo/Eric Gay)

Green Party presidential candidate Jill Stein (center) and vice presidential candidate Cheri Honkala sit at the entrance to Hofstra University on Tuesday after being informed that they wouldn't be able to enter and participate in the second presidential debate. (AP Photo/Mary Altaffer)

Hofstra University senior Rick Theroux, 21 (right), holds up a sign among fellow students as they stand in the background of a live television news show on Tuesday ahead of the debate. (AP Photo/David Goldman)

Williams Martinez (left) and Kirt Gallatin lift a two-story-high sign in preparation for the debate on Tuesday. (AP Photo/Eric Gay)

Mitt Romney is greeted as he steps off his campaign plane in Ronkonkoma, N.Y., on Tuesday as he arrived for his debate against President Obama. (AP Photo/Charles Dharapak)

President Obama greets people as he arrives at John F. Kennedy International Airport in New York City on Tuesday en route to Hempstead, N.Y., for the debate. (AP Photo/Carolyn Kaster)

Billy Koske (left) and Jose Reyes hang a sign in the media filing center in preparation for the debate. (AP Photo/Charlie Neibergall)

A worker prepares a set in the media filing center on Monday in preparation for Tuesday's presidential debate at Hofstra University in Hempstead, N.Y. (AP Photo/Eric Gay)

Stand-ins for Mitt Romney (left) and President Obama (right) run through a rehearsal on Monday with moderator Candy Crowley (foreground) ahead of Tuesday's presidential debate. (AP Photo/David Goldman)

A screen shows photos of Mitt Romney and President Obama as a television news crew prepares in the background for the debate. (AP Photo/David Goldman)

Erica Andiola (left), who is originally from Mexico and currently lives in Mesa, Ariz., speaks during a news conference at Hofstra University on Monday. The conference was held as a callout to President Obama and Mitt Romney to talk about their immigration policies during Tuesday's debate. (AP Photo/Mary Altaffer)

Hofstra Public Safety officer Ronald Nardo watches as stand-ins for Mitt Romney (rear left) and President Obama (right) run through a rehearsal on Monday ahead of Tuesday's presidential debate. (AP Photo/David Goldman)

Long Beach High School student Odir Hernandez, 17 (left), has his photo taken by classmate Frank Valdez, 16, during a tour on Monday ahead of Tuesday's debate. (AP Photo/David Goldman)

Security personnel gather outside the debate hall on Monday ahead of Tuesday's debate. (AP Photo/David Goldman)