KEY POINTS
  • Democratic Rep. Ruben Gallego of Arizona launched his campaign for the U.S. Senate seat currently held by Sen. Kyrsten Sinema.
  • The announcement makes Gallego, a Marine Corps veteran who has represented the Grand Canyon State in the U.S. House since 2015, the first candidate in what could be a three-way race for Sinema's seat.
  • Formerly a centrist Democrat, Sinema switched to become an independent after the midterms, when Democrats extended their gains in the Senate.
Representative Ruben Gallego, a Democrat from Arizona, speaks during a House Armed Services Committee hearing in Washington, D.C., U.S, on Thursday, July 9, 2020.

Democratic Rep. Ruben Gallego of Arizona on Monday launched a 2024 campaign for the U.S. Senate seat held by Sen. Kyrsten Sinema, who recently left the Democratic Party and faces an uncertain political future.

"I will be challenging Kyrsten Sinema for the United States Senate, and I need all of your support," the 43-year-old Gallego said in a video posted Monday morning.