Jimmy P. Hoffa’s International Brotherhood of Teamsters (IBT), as well as the International Brotherhood of Boilermakers (IBB) opposed the endorsement of Democratic nominee Hillary Clinton, according to newly released emails from Wikileaks.

The powerful North American Building Trades Union (NABTU) endorsed Clinton in December. The two large affiliate unions, the Teamsters and the Boilermakers, sent individual letters to the president of the NABTU, stating their opposition to the endorsement vote.

An email released by WikiLeaks from Hillary for America’s labor outreach director, Nikki Budzinski, to Clinton’s campaign chairman John Podesta and other campaign officials revealed the situation.

“Hi guys I wanted to flag for you both of these letters that the Building Trades sent over to me today,” the email starts out. “After their [NABTU] endorsement vote, the Teamsters and Boilermakers today sent individual letters (attached) to President Sean McGarvey stating their opposition to the endorsement vote,” Budzinski continued.

Budzinski wanted to prepare the campaign for any potential leaks and assured the campaign that, “In case someone leaks a letter to the press I have added Jesse.” Budzinski is most likely referring to Jesse Ferguson, deputy national press secretary and senior spokesman for the campaign.

[dcquiz] The leaked email highlights Clinton’s challenge to rally the support of rank and file union members, who have been a solid part of the Democratic Party base in recent decades. While national union bosses have come out in support of Clinton, it does not guarantee support from other members.

“First, they colluded with the DNC and mainstream media to stop Bernie Sanders and his supporters, or as Hillary calls them, hopeless ‘basement dwellers,'” Scott Hagerstrom, Republican nominee Donald Trump’s campaign director for union-heavy Michigan, told The Daily Caller News Foundation. “Now we have proof Hillary also tried to silence rank and file union members with strong arm tactics. There is clearly no level to which Hillary will not stoop to retain her power.”

In the summer of 2015, labor groups at the national level started lining up behind Clinton

The Teamsters and the Boilermakers did not respond to the TheDCNF’s requests for comments.

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