PHOENIX (AP) — Daniel Hernandez Jr., the intern hailed as a hero for helping save the life of then-U.S. Rep. Gabrielle Giffords following an attempted assassination a decade ago, announced Thursday he's running to represent her former district in Congress.

Hernandez was a 20-year-old college student in his first week interning for Giffords when he went to her “Congress on your corner” constituent event where a gunman opened fire killing six and injuring 13, including Giffords, in 2011. He kept the congresswoman conscious and applied pressure to her head wound until paramedics arrived.

His actions were widely praised during a period of shock and unity that gripped the nation. Then-President Barack Obama called Hernandez a hero at a memorial for the victims and also while he a guest at the State of the Union address weeks later.

A Democrat, Hernandez currently represents parts of Tucson in the state House of Representatives. He's developed a moderate profile as one of a handful of Democrats who occasionally cross the aisle to work with Republicans, sometimes to the frustration of more progressive members of his party.

“Gabby Giffords continues to inspire me and I strive to follow her example of service for our community,” Hernandez said in a statement announcing his candidacy.

A trauma surgeon who operated on Giffords that day, Dr. Randy Friese, is also running for the former Giffords seat. He now serves with Hernandez in the House. State Sen. Kirsten Engel is also seeking the Democratic nomination.

Arizona's 2nd Congressional District has historically been one of the most competitive in the state. It currently covers parts of Tucson, stretching to the state's borders with Mexico and New Mexico, but the boundaries will change before next year's election due to the every-decade redistricting.