Sen. Bernie Sanders on Capitol Hill on May 17. (Photo: Alex Brandon/AP)

WASHINGTON — The Democratic National Committee’s rules and bylaws committee adopted a new rule on Friday that would prevent outsiders like Bernie Sanders from seeking the party’s nomination in the 2020 presidential race. The move seems to be the latest salvo in the ongoing jockeying over the party’s future that emerged following the at times bitter primary battle between Hillary Clinton and Sanders in 2016.

But while the rule change left some of Sanders’s top allies thinking the party was being driven by “spite,” it likely won’t affect him directly and could pave the way for one of his favorite reforms.

DNC member Randi Weingarten, who is president of the American Federation of Teachers, posted a photo of the rules change shortly after it was added to the proposed draft call for the 2020 Democratic convention. Weingarten, who attended Friday’s DNC meeting in Providence, R.I., wrote that the party “changed the rules to ensure to run for President as a Democrat you need to be A Democrat.”

The new rule would force candidates in Democratic presidential primaries to state that they are Democrats, accept the party’s nomination if they win the 2020 primary and to “run and serve” as a member.

“At the time a presidential candidate announces their candidacy publicly, they must publicly affirm that they are a Democrat,” the rule says. “Each candidate pursuing the Democratic nomination shall affirm, in writing, to the National Chairperson of the Democratic National Committee that they: A. are a member of the Democratic Party; B. will accept the Democratic nomination; and C. will run and serve as a member of the Democratic Party.”

The rule seems like a clear response to Sanders, who caucuses with Democrats in the Senate but has steadfastly maintained his status as an independent. Sanders ran to the left of Clinton and identifies himself as a “democratic socialist.”

Hillary Clinton and Bernie Sanders interrupt each other during a Democratic presidential debate in January 2016. (Photo: Mic Smith/AP)

During the 2016 primary, Clinton and her supporters regularly criticized Sanders for his lack of an official affiliation with the party. After an unexpectedly close race, Sanders ultimately lost to Clinton. His base of support included younger voters and independents, whom many Democrats see as vital to the party if it hopes to avoid a repeat of its defeat to Trump in 2016. Many Sanders supporters angrily felt the DNC stacked the deck in Clinton’s favor, a perception that was amplified by hacked emails from party leaders that were published by Wikileaks in the lead-up to the party’s 2016 convention.

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In the wake of Clinton’s loss to Trump, the party assembled a unity commission with members appointed by both Clinton and Sanders. The Sanders wing focused on recommendations designed to open up the party’s nominating process and make it more inclusive to what Sanders termed “the working people and young people of our country.” One of the commission’s proposals that was particularly important to Sanders was the elimination of the unelected Democratic superdelegates who are able to vote for a nominee regardless of who won the race in their home state. Sanders and many of his supporters viewed these superdelegates as a way for the Democratic Party establishment to control the nominating process irrespective of the will of the party’s voters.

With Sanders’s independent status and push for inclusivity, the new rule change would seem to be a slap in the face and a potential roadblock should the Vermont senator decide to mount another presidential run in 2020. However, Sanders allies do not believe he would be affected by the measure thanks to a unique rule in his home state.

Sanders, who is currently running for reelection, typically runs in the state’s Democratic primary but declines the party’s nomination after winning. The move allows him to fend off Democratic challengers in the state while still running as an independent. Last month, the Vermont Democratic Party passed a resolution supporting this strategy and proclaiming that Sanders would still be considered a member of the party “for all purposes and entitled to all the rights and privileges that come with such membership at the state and federal level.” That membership could inoculate him against the DNC’s rules change.

Bernie Sanders speaks at a rally for Hillary Clinton in Raleigh, N.C., on Nov. 3, 2016. (Photo: Andrew Harnik/AP)

Even if Sanders himself would be unaffected by the shift, one of his top allies expressed dismay at the new rule. Mark Longabaugh, who was a senior adviser to Sanders’s 2016 presidential campaign, told Yahoo News he was baffled by the party’s decision.

“I don’t have any worries that Bernie Sanders could meet the criteria to run as a Democrat in 2020, but it always puzzles me that there are some Democrats who want to do this and promote this. I scratch my head and ask why they would want to make the party more narrow and more exclusive,” Longabaugh said.

Longabaugh suggested the move could only have been motivated by lingering animus from the primary race between Clinton and Sanders.

“We just came off a devastating presidential loss in 2016. It would seem to me the actual impetus would be to expand the Democratic Party. I just for the life of me don’t see any motivation for this beyond personal spite,” said Longabaugh.

Jeff Weaver, who was Sanders’s campaign manager, similarly expressed confidence that Sanders wouldn’t be affected by the rules change. However, Weaver also suggested it was to exclude people from the party’s presidential nominating process.

“Do they really want Bernie and millions outside the party?” Weaver asked in a text message.

One source familiar with the discussions told Yahoo News the rules change was not aimed at Sanders and wouldn’t necessarily affect him. In fact, the source described it as a step that was designed to make it easier for party leaders to accept one of Sanders’s main priorities — the end of superdelegates.

Committee members are continuing to discuss the proposal to eliminate superdelegates. They will meet again to make a final vote on the proposal in the coming weeks before all proposed changes head to the DNC for a final vote in August.

“With the full DNC heading toward the path of essentially eliminating superdelegates on the first ballot, people felt this would help garner support for the superdelegate proposal,” the source said.

Last December, DNC Chairman Tom Perez told Yahoo News he was open to proposals to drastically reduce the number of superdelegates.

Maria Cardona, a veteran strategist who has worked for Clinton, was one of the backers of the rules change.

“The entire committee backed this. It was unanimous,” Cardona told Yahoo News in a text message, adding, “It was done to ensure that the presidential nominee of the Democratic Party is actually a Democrat.”

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