Sanders told reporters he believes "there is a very good chance” that Manchin, a West Virginia Democrat, and Sinema, a Democrat from Arizona, could face challenges in their states' Democratic primaries. He suggested home-state voters would be disappointed that the pair have refused to support changing Senate rules to overcome a Republican filibuster against major voting legislation while also balking at a massive, Biden-backed spending and social plan known as Build Back Better.
Asked if he'd consider supporting such primary challengers, Sanders affirmed, “Well, yeah."
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Sanders, a Vermont Independent who caucuses with Senate Democrats, didn't elaborate on his comment, though it is unusual for senators to suggest they'd be willing to campaign against colleagues from their own party. The move recalls more of the bare-knuckled politics of former President Donald Trump, who has gleefully targeted fellow Republicans in Congress he sees as disloyal.
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Sanders' sentiments also lay bare Progressives' growing frustrations with the more moderate Manchin and Sinema, whom the left has blamed for stalling many of Biden’s top legislative priorities.
Manchin countered that he wouldn't be rattled by a primary challenger.
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“I’ve been primary my entire life. That would not be anything new for me,” he said Tuesday, when asked about fellow Democrats urging voters not to back him in a primary. “I’ve never run an election before since I wasn't in the primary. This is West Virginia, it’s rough and tumble. We’re used to that. So bring it on.”
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Sanders remains at the top of the list of the nation's leading Progressive voices after strong Democratic presidential primary bids in 2016 and 2020. Sanders is still nationally popular enough to potentially affect Senate primaries around the country.
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Manchin and Sinema aren't up for reelection until 2024, but both could face serious primary challengers then. Democratic Rep. Ruben Gallego of Arizona, who has sharply criticized Sinema for not supporting the voting rights legislation, hasn't ruled out launching a challenge against her.
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Earlier Tuesday, Emily's List, a group that works to elect women nationwide and has deep ties to Democrats, announced it would no longer endorse Sinema if she failed to support changing Senate rules to advance the voting legislation.
NARAL Pro-Choice America, which supports abortion rights and is also influential in top Democratic circles, released its own statement suggesting it would no longer support or endorse Manchin or Sinema because of their stances on the legislation.