Republican vice presidential candidate Paul Ryan visits the Fredericksburg Expo and Conference Center in Fredericksburg, Va., on Oct. 16, 2012. (Associated Press/The Free Lance-Star)
Republican vice presidential candidate Paul Ryan greets supporters while visiting the Fredericksburg Expo and Conference Center in Fredericksburg, Va., on Oct. 16, 2012. (Associated Press/The Free Lance-Star)
People cheer as Republican vice presidential candidate Paul Ryan visits the Fredericksburg Expo and Conference Center in Fredericksburg, Va., on Oct. 16, 2012. (Associated Press/The Free Lance-Star)
Republican vice presidential candidate Paul Ryan greets supporters while visiting the Fredericksburg Expo and Conference Center in Fredericksburg, Va., on Oct. 16, 2012. (Associated Press/The Free Lance-Star)
**FILE** Republican vice presidential candidate Paul Ryan visits the Fredericksburg Expo and Conference Center in Fredericksburg, Va., on Oct. 16, 2012. (Associated Press/The Free Lance-Star)
A Secret Service agent stands guard at right as Republican vice presidential candidate, Rep. Paul Ryan, R-Wis. speaks during a rally at Automated Conveyor Systems in Lynchburg, Va., Tuesday, Oct. 16, 2012. (AP Photo/Steve Helber)
Republican vice presidential candidate, Rep. Paul Ryan, R-Wis., speaks at a rally at Automated Conveyor Systems in Lynchburg, Va., Tuesday, Oct. 16, 2012. (AP Photo/Steve Helber)
Supporters of Republican vice presidential candidate, Rep. Paul Ryan, R-Wis., wave flags during a rally at Automated Conveyor Systems in Lynchburg, Va., Tuesday, Oct. 16, 2012. (AP Photo/Steve Helber)
Republican vice presidential candidate, Rep. Paul Ryan, R-Wis. poses for a photo while serving up Montgomery Inn barbeque, Monday, Oct. 15, 2012, at a campaign rally in Cincinnati. (AP Photo/Al Behrman)
Republican vice presidential candidate, Rep. Paul Ryan, R-Wis., center, serves up Montgomery Inn barbeque, Monday, Oct. 15, 2012, during a campaign stop at Lunken Airport in Cincinnati. (AP Photo/Al Behrman)
Republican vice presidential candidate Paul Ryan speaks Oct. 16, 2012, during a rally at Automated Conveyor Systems in Lynchburg, Va. (Associated Press)
**FILE** Republican presidential candidate Mitt Romney (left on stage) is introduced by his running mate Paul Ryan as Sen. Rob Portman, Ohio Republican, watches during a Oct. 12, 2012, campaign event in Lancaster, Ohio. (Associated Press)
Republican vice presidential nominee Rep. Paul Ryan of Wisconsin and Vice President Joe Biden pass each other after the vice presidential debate at Centre College, in this Oct. 11, 2012 photo taken in Danville, Ky. (AP Photo/Charlie Neibergall, File)