WASHINGTON — Rep. Ruben Gallego, D-Ariz., is expected to announce Monday that he will run for the Arizona Senate in 2024, according to a source familiar with his planned pitch.

Gallego’s announcement had long been rumored to be by the end of January, and Newsweek was the first to report the plan for Monday.

The decision comes after Sen. Kyrsten Sinema, I-Ariz., high-fived Sen. Joe Manchin, DW.Va., at the World Economic Forum in Davos, Switzerland, this week to celebrate blocking a review of filibuster in the Democratic Party. controlled senate.

Gallego, a progressive Democrat, is running for the seat held by Sinema, who decided in December to leave the Democratic Party and become independent. Sinema’s six-year term ends at the end of next year, but he has not yet said whether he plans to run for re-election. If he does, and Gallego wins the Democratic nomination, they would face each other in the general election.

In December, after Sinema announced she was changing her party affiliation, Gallego told NBC News that she would likely run for Senate.

«I’m a good Marine, so I’ve been preparing for this, bringing people in, meeting the right people and, you know, making sure that we can do, so that I can, you know, go immediately. [when] We made a decision,» he said.

Gallego went on to say that he believes that if Sinema runs, it will «almost ensure the fact that the Senate seat will remain in Democratic hands» because of the GOP’s struggles to keep their coalition together. That, however, would not be a sure thing.

Meanwhile, several Republicans are weighing up the races, including Kari Lake and Blake Masters, who lost the gubernatorial and senate races, respectively, in 2022. That list also includes Jim Lamon, a solar energy executive who lost the Republican primary to Masters last year.

Gallego, 43, is a US Navy combat veteran who served in the Iraq war. Before coming to the House in 2015, he previously served as a member of the Arizona state House.

Bridget Bowman Y ben kamisar contributed.