MICHEL MARTIN, HOST:
Democrats woke up Friday to the news that one of its members had fled for more independent pastures. Arizona senior Senator Kyrsten Sinema announced that she left the Democratic Party and registered as an independent. That move came just days after Democrats were celebrating their win in the Georgia runoff, when Senator Raphael Warnock held off a stiff challenge from a Trump-backed challenger. And it complicates things for Democrats who were once again left with a razor-thin majority in the Senate. But although many in the national political universe seem shocked, some people, especially in Arizona, weren't surprised at all. From member station KJZZ, Michel Marizco has this report.
MICHEL MARIZCO, BYLINE: The signs were already there when President Joe Biden traveled to Arizona earlier this week.
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PRESIDENT JOE BIDEN: Special thanks to the incredible Arizona Democratic members of Congress who flew out with me today from Washington.
MARIZCO: Joined by Arizona's congressional delegation, one was most notable by her absence - Arizona Senator Kyrsten Sinema.
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BIDEN: And I want to thank Senator Sinema, who can't be with us today. She's in Washington.
MARIZCO: Here's how Arizona's Chamber of Commerce CEO Danny Seiden put it.
DANNY SEIDEN: She was the only member of the delegation not present, so there's a lot of clues.
MARIZCO: Sinema, who has served in Congress for nearly a decade, surprised many when she announced she would no longer wear the title of Democrat. But others who worked with her for a long time were not surprised.
RAUL GRIJALVA: Not overly, no. I think it was a predictable move.
MARIZCO: The longest-serving member of Arizona's congressional delegation, Democratic Congressman Raul Grijalva, said Sinema would have faced a tough primary in 2024.
GRIJALVA: Given the reaction of Democrats to the positions that she'd been taken as senator and some of the things that she's held up and demanded changes to that, by far, Democrats and most people supported.
MARIZCO: One of the Democrats who might have challenged Sinema in 2024 is Congressman Ruben Gallego. He was quick to release a statement on Friday saying Sinema is, quote, "putting our own interests ahead of those of Arizonans." As for how this will impact the upcoming Congress, Sinema will keep her four committee seats and told POLITICO she will not caucus with the Republican Party. Sinema told KJZZ changing her political affiliation was a natural path forward.
KYRSTEN SINEMA: When I ran for the Senate back in 2018, I promised Arizonans I'd be an independent voice for our state. That's exactly what I've done. And so I think today's decision and announcement is just a reflection of that.
MARIZCO: Arizona has a unique voter makeup, where a third of voters are Democrats, a third are Republicans, and a third don't affiliate with either party. Political strategist Chuck Coughlin says candidates in Arizona typically win with high percentages of their own party and then a plurality of those unaffiliated voters.
CHUCK COUGHLIN: That rule's out the window now. What percentage of Democrats is she going to get? What percentage of Republicans is she going to get? And what's your ceiling with unaffiliated voters? That becomes a calculus for anybody else running.
MARIZCO: As an independent, Sinema will have to build a whole new coalition of voters from all three groups to be viable.
COUGHLIN: It's just never been done. That's what's fascinating about it.
MARIZCO: How this move will play out is still uncertain, but one thing is clear - the 2024 Senate race is underway in Arizona. For NPR News, I'm Michel Marizco in Flagstaff, Ariz. Transcript provided by NPR, Copyright NPR.