Sen. Kyrsten Sinema announced Tuesday that she will not run for reelection later this year.
The senator from Arizona, who changed party affiliation from Democrat to Independent in 2022, cited hyper-partisanship as a reason to leave Congress when her term is up at the end of this session.
"The only political victories that matter these days are symbolic, attacking your opponents on cable news or social media," she said. Compromise is a dirty word."
Sinema first took office in 2019, winning the seat previously held by Republican Jeff Flake. Her victory made history as she became the first openly bisexual woman to be elected to Congress.
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Despite initially being a Democrat, Sinema was always considered an independent thinker, often citing former Arizona Sen. John McCain in her approach to politics.
While she still caucused with Democrats, Sinema was known for working with members of the GOP, including on the recent border security framework, which Republicans ultimately derailed.
Sinema was facing a tough reelection campaign even if she would have decided to run. Democratic Rep. Ruben Gallego and former Arizona gubernatorial candidate Kari Lake have announced their intentions to run for the seat.
Democrats are trying to hold on to power in the U.S. Senate. They currently have a 51-49 edge.