Republican presidential candidate, former Massachusetts Gov. Mitt Romney waves to supporters as he arrives for a campaign stop at the Wisconsin Products Pavilion at State Fair Park in West Allis, Wis., November 2, 2012.

Republican presidential candidate, former Massachusetts Gov. Mitt Romney gestures as he speaks at a campaign event at Integrity Windows in Roanoke, Va., November 1, 2012.

Republican presidential candidate, former Massachusetts Gov. Mitt Romney gestures as he takes the stage for a campaign event at Meadow Event Park, Doswell, Va., November 1, 2012.

Republican presidential candidate former Massachusetts Gov. Mitt Romney, right, speaks during a campaign event along with his vice presidential running mate Rep. Paul Ryan, R-Wis., left, at the Celina High School gymnasium in Celina, Ohio, October 28, 2012.

Republican presidential candidate Mitt Romney addresses the media prior to a breakfast fundraiser in Salt Lake City, June 23, 2007.

Ann Romney, at center left in blue suit, sits with her family as Gov. Mitt Romney announces his candidacy for president at The Henry Ford Museum in Dearborn, Mich., February 13, 2007.

Massachusetts Gov. Mitt Romney introduces his wife, Ann, at the State Republican convention in Concord, N.H., September 30, 2006.

Massachusetts Gov. Mitt Romney addresses a gathering regarding electronic medical records at the Ether Dome at Massachusetts General Hospital in Boston, December 6, 2004.

Massachusetts Gov. Mitt Romney addresses reporters at the Statehouse in Boston, after Massachusetts' highest court ruled 4-3 Tuesday that the state's ban on same-sex marriage is unconstitutional, November 18, 2003.

Mass. Gov. Mitt Romney, front right, proposed legislation to hike the fines for companies that spill oil or other toxic substances into Massachusetts waters, May 20, 2003.

Mitt Romney, accompanied by Lt. Gov.-elect Kerry Healy, takes the oath of office as governor of Massachusetts at the Statehouse in Boston, January 2, 2003.

Massachusetts Republican gubernatorial candidate Mitt Romney waves to supporters and media in Boston after making his victory speech, November 5, 2002.

Massachusetts Republican gubernatorial candidate Mitt Romney speaks during a news conference in front of the Statehouse in Boston, October 3, 2002.

Mitt Romney, the new boss of the Salt Lake Organizing Committee, outlines his plans to spend no more money than the Olympics take in, Feb. 11, 1999.

Thomas S. Monaghan, founder and chairman of Domino's Pizza, Inc., left, and Mitt Romney, managing director of Bain Capital, Inc., sign an agreement for Monaghan to sell a "significant portion" of his stake in the company to Bain Capital in New York, September 25, 1996.

Republican U.S. senatorial candidate Mitt Romney greets supporters at the Columbus Day parade in Worcester, Mass., following his father's path into politics, October 10, 1994.

Ann Lois Davies and Willard Mitt Romney, second and youngest son of former Michigan Governor and Mrs. Lenore Romney, married in a civil ceremony at the brides family home in Bloomfield Hills, Mich., March 21,1969.

Gov. George Romney and his son, Mitt, look out over the New York World's Fair grounds from the heliport after attending a Michigan breakfast at the Top of the Fair Restaurant, May 18, 1964.