Retired Navy captain and astronaut Mark Kelly, the husband of former U.S. Rep. Gabrielle Giffords, speaks during a news conference in favor of proposed gun control legislation at the St

 

              Retired Navy captain and astronaut Mark Kelly, the husband of former U.S. Rep. Gabrielle Giffords, speaks during a news conference in favor of proposed gun control legislation at the St
Retired Navy captain and astronaut Mark Kelly, the husband of former U.S. Rep. Gabrielle Giffords, speaks during a news conference in favor of proposed gun control legislation at the State Capitol, in Denver, Monday March 4, 2013. Behind him are, far left to right, Karina Sartiaguin, 18, who was shot in the back outside her high school in 2010, Tom Mauser, the father of Columbine High School shooting victim Daniel Mauser, Patricia Maisch, who helped take away a magazine from the Tucson shooter, Dave Hoover, the uncle of 18-year-old AJ Boik, one of 12 people killed in the Aurora theater shooting, and AJ Boik's mother Theresa Hoover. (AP Photo/Brennan Linsley)