Former astronaut Mark Kelly (from left), former Rep. Gabrielle Giffords, Ron Barber and Nancy Barber gather during a get-out-the-vote rally for Mr. Barber at the Rialto Theater in downtown Tucson, Ariz., on Saturday, June 9, 2012. (AP Photo/Arizona Daily Star, Mamta Popat)

Photo by: Mamta Popat

Former astronaut Mark Kelly (from left), former Rep. Gabrielle Giffords, Ron Barber and Nancy Barber gather during a get-out-the-vote rally for Mr. Barber at the Rialto Theater in downtown Tucson, Ariz., on Saturday, June 9, 2012. (AP Photo/Arizona Daily Star, Mamta Popat)