Columnist

When Bernie Sanders launched his bid for the Democratic nomination, he was often asked whether he, a democratic socialist, would actually become a Democrat. Now, more than a year after he ignited a movement with his unsuccessful bid, that question is moot. The Democrats have become socialists.

This became official, more or less, Wednesday afternoon, when Sanders rolled out his socialized health-care plan, Medicare for All, and he was supported by 16 of his Senate Democratic colleagues who signed on as co-sponsors, including the party's rising stars and potential presidential candidates in 2020: Elizabeth Warren. Cory Booker. Kamala Harris. Kirsten Gillibrand.

Several of them dutifully joined Sanders, who is threatening another presidential run himself, at the rollout event in one of the largest hearing rooms on Capitol Hill and praised the guru of the single-payer movement for government-run universal health care.

"I'm all in on this. Thank you, Bernie," said Sen. Jeff Merkley (Ore.).

Gillibrand (N.Y.): "I will be standing with Bernie."

Warren (Mass.): "I want to say thank you to Bernie for all that you have done."

"The reason we have a chance to achieve" single-payer health care, said Sen. Richard Blumenthal (Conn.), "is because of advocates like Bernie Sanders and Elizabeth Warren."

This is a dramatic shift. In 2013, when Sanders introduced similar legislation, he didn't have a single co-sponsor. By contrast, you could have been forgiven for thinking Wednesday's rollout, with Sanders, Warren, Booker, Harris and Gillibrand testing their messages, was the first Democratic cattle call of the 2020 campaign. There were a couple hundred liberal activists in the room (many of them veterans of the Sanders campaign and a few wearing "Join the Political Revolution" Sanders T-shirts) and another 50 in an overflow room.

This embrace of an unabashedly socialist position by the Democrats delights nobody more than the original socialists, the Democratic Socialists of America. David Duhalde, the group's deputy director, was one of the first in line for the event, carrying a Medicare-for-All sign.

"Socialism has been most successful in this country when its ideas have been adopted by other parties," he said, listing the enactment of labor laws, Social Security and Medicare. But "this is a high water mark," he said.

In the short term, I've argued, this development is a bad thing for Democrats. The nation's focus has been on divisions among Republicans and their inability to enact any sort of agenda under President Trump. The single-payer issue highlights Democratic divisions and united Republicans.

Notably, only one Democrat who faces a competitive reelection, Sen. Tammy Baldwin (Wis.), signed on with Sanders. The socialized-medicine bill is popular with the Democratic base but is a liability for Democratic candidates in the swing districts and Republican states that Democrats need to win to retake the House and Senate.

The divisions were on display Wednesday: As Harris spoke, a member of the left-wing group Code Pink held up a large cutout of the head of Sen. Dianne Feinstein (D-Calif.), who is up for reelection and doesn't support the Sanders bill. Beneath Feinstein's photo were the words "Healthcare Denier." (Luckily for Democrats, Sanders told The Washington Post's David Weigel that he doesn't plan to make the issue a litmus test.)

The Republican National Committee, seizing the rare opportunity to play offense, sent out a news release and a video attacking the plan: "Legislation does NOT include how to pay for the $32 trillion program. . . Plans of 156M(!!) Americans would be upended." And Sen. Lindsey O. Graham (R-S.C.), announcing yet another attempt at repealing Obamacare on Wednesday, tried to use the Sanders plan to revive the moribund effort. He said his bill was Republicans' "best and only chance" to prevent single-payer health care.

It's not hard to see Graham's prophecy coming true over time, particularly if Republicans, unable to replace Obamacare, continue to sabotage the program and let it fall apart, leaving millions without health care. Republicans have another problem fighting single-payer care now. Because they called Obamacare "socialized medicine," even though it's a market-based plan, they have nothing worse to fire at Democrats for embracing the real thing.

Sanders lost the nomination battle to Hillary Clinton (who favored a more incremental approach to health care and gives the single-payer debate little mention in her new book about the campaign). But he seems to be winning the war over the direction of the Democratic agenda. Sanders now has 35 percent of the Senate Democratic Caucus, and some of the biggest names in the party, embracing his call. So when he predicts, as he did Wednesday, that "this nation, sooner than people believe, will in fact pass a Medicare-for-All, single-payer system," it doesn't sound as crazy as it once did.

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