WASHINGTON — Retired astronaut Mark Kelly, who became a staunch gun-control activist after the shooting of his wife, former Rep. Gabrielle Giffords, says he's running to finish John McCain's term in the U.S. Senate.

  • Mark Kelly announces run for John McCain's Senate seat
  • Ex-NASA astronaut has become staunch gun-control advocate
  • His wife, former Rep. Giffords, was shot during public appearance

Kelly, who has never held elected office, announced his plans in a video message he tweeted Tuesday.

Giffords survived being shot in the head during a constituent event in Tucson eight years ago.

Kelly is a top Democratic recruit to challenge Republican Sen. Martha McSally, who was appointed to the seat late last year. The race is widely expected to be one of the most closely contested Senate races of the 2020 election.

Kelly is a retired Navy captain who flew four missions in space between 2001 and 2011. Since Giffords survived the 2011 assassination attempt, the pair cofounded Americans for Responsible Solutions PAC, speaking at gun-control events and in front of legislatures to push for stronger background checks and domestic violence protections.

In September 2016, Kelly and Giffords kicked off a six-week national tour in Orlando — which was still reeling from the Pulse nightclub shooting months before — to urge voters to push for gun control laws and reduce gun violence. They were joined by Pulse survivors and local leaders at a gun violence roundtable at the Dr. Phillips Center.

The 2020 election will decide who finishes the last two years of McCain's term. The winner would have to run again for a full six-year term in 2022.

Information from the Associated Press was used in this report.

In a video tweeted Tuesday, Mark Kelly announces a run for John McCain's Senate seat. Kelly is a top Democratic recruit. (Screen capture from Twitter)
In a video tweeted Tuesday, Mark Kelly announces a run for John McCain's Senate seat. Kelly is a top Democratic recruit. (Screen capture from Twitter)