Popular Democratic Congressman Launches Bid to Unseat Arizona Sen. Kyrsten Sinema in 2024

Ruben Gallego, Kyrtsen Sinema
Ruben Gallego, Kyrtsen Sinema

Tom Williams/CQ-Roll Call, Inc via Getty; Anna Moneymaker/Getty

Democratic Rep. Ruben Gallego has officially announced he'll run for U.S. Senate in 2024 against incumbent Kyrsten Sinema, who recently left the Democratic Party to become an independent.

In a tweet posted Monday, Gallego, 43, wrote: "Growing up poor, all I had was the American dream. It kept me going: as a kid sleeping on the floor, a student scrubbing toilets, a Marine losing brothers in Iraq. Today, too many Arizonans see their dream slipping away. I'm running for the U.S. Senate to win it back for you!"

Along with his tweet, Gallego published a campaign video, in which he describes being born to an immigrant mother who raised him and his three siblings as a single mom, and attending Harvard University and serving as a U.S. Marine before entering politics.

RELATED: Arizona Sen. Kyrsten Sinema Leaves Democratic Party to Become Independent: 'Right for the Country'

Gallego currently serves the U.S. representative for Arizona's 3rd congressional district, encompassing parts of Phoenix and Glendale.

Gallego—who came to office in 2015 and previously served in Arizona's state House—is, according to one poll, "considerably more popular than Sinema and would be a top tier Senate candidate regardless of what she decides to do in 2024."

RELATED: Progressive Independent Bernie Sanders Attributes Kyrsten Sinema's Party Switch to 'Political Aspirations'

Sinema, who has positioned herself as one of Senate's biggest disruptors since being elected in 2018, announced in December that she had become an independent, saying her decision was one one made with constituents in mind.

"There's a disconnect between what everyday Americans want and deserve from our politics, and what political parties are offering," Sinema argued in an op-ed written for The Arizona Republic.

With her switch, Sinema will now become one of only three independent U.S. senators, joining Vermont Sen. Bernie Sanders and Maine's Angus King, both of whom also caucus with the left and contribute to the Democratic Party's technical majority in Senate.

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Sinema's move is unlikely to shift the power balance in the Senate, where Democrats hold a majority, though it could have an impact on her career in Arizona, particularly with Gallego announcing his campaign.

In a statement released following Sinema's announcement of her party switch, Gallego said Sinema was "once again putting her own interests ahead of getting things done for Arizonans." Rumors quickly began swirling that he was mulling a run for her seat.