WASHINGTON – Workers on Vermont Sen. Bernie Sanders' campaign voted to unionize on Friday, becoming what is possibly the first presidential campaign staff in history to organize.

A majority of the Democrat's staff signed on to unionize, meaning all current and future employees would be part of the bargaining process for better pay and benefits. The workers, everyone below the title of deputy director, will be represented by United Food and Commercial Workers Union (UFCW) Local 400, which represents about 35,000 employees in six states and the District of Columbia.

Jonathan Williams, a spokesman for the UFCW, said to his knowledge the Sanders campaign is the first to unionize in history, marking a new path that could be used for campaigns for years to come.

"The best time to join a union is always now," Williams said. "High working standards should be the standard and I would certainly call upon every presidential campaign to look toward the leadership Bernie Sanders' campaign has shown."

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Williams said the next steps are for workers to set up negotiations, something he said would have to happen very soon due to it being a campaign. The UFCW said the agreement could grow to more than 1,000 workers throughout Sanders' 2020 campaign. Employees who transition to the White House, if Sanders were to win, would not be members of the union.

"I hope this breakthrough serves as a model for other presidential campaigns, as well as party committees and candidates for other offices," UFCW Local 400 President Mark Federici said in a statement. "While political campaigns aren’t the easiest work environment, every worker has the right to respect and dignity."

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In January, Sanders apologized after multiple women said allegations of sexual assault within his campaign were not properly addressed during his 2016 bid for president.

The allegations from multiple women who worked on Sanders' campaign surfaced in the New York Times, which criticized Sanders' campaign for not adequately addressing incidents of sexual harassment, sexist mistreatment and pay disparities between men and women.

On CNN, Sanders apologized to "any woman who feels like she was not treated appropriately." When asked if he had been aware of the complaints, Sanders said, "I was a little bit busy running around the country trying to make the case (to be elected as president)."

The allegations and his perceived failure to rectify the issues, female campaign workers told the Times, bring into question whether he can fight for women's interests if he again seeks the presidency.

"I am not going to sit here and tell you that we did everything right in terms of human resources, in terms of addressing the needs that I'm hearing from now, that women felt they were disrespected, that there was sexual harassment which was not dealt with as effectively as possible," Sanders said on CNN.

The UFCW said Sanders' campaign stayed neutral in the unionizing process. Sanders' campaign manager, Faiz Shakir, wrote on Twitter the campaign was "very proud" of the unionizing effort.

"Bernie Sander is the most pro-union candidate in the field, he'll be the most pro-union president in the White House and we're honored that his campaign will be the first to have a unionized workforce," Shakir said.