It took all but two days after the Georgia Senate runoff — which gave Democrats a 51-49 edge — for Arizona Sen. Kirsten Sinema to throw a wrench in the new majority's makeup. The first-term lawmaker announced last Friday she was leaving the Democratic Party to become an independent. For now, she will keep her committee seats assigned by Democrats even though she doesn't plan on going to caucus meetings (like the other Democratic-aligned independents Bernie Sanders and Angus King do) so there will be functionally no change in party control.

Sinema's change in alignment comes just as the 2024 Senate map — already brutal for Democrats — is coming into focus. She was already going to face a bruising primary where she was the underdog to win re-nomination, given how many times she's infuriated her now-former caucus and the more liberal wing of the party, many of whom helped her in 2018 turn Arizona's Senate seat blue for the first time in more than 40 years.

However, her odds for re-election were already bleak, with Rep. Ruben

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