The move has been called “humiliating” for Harris. The powerful labor union has previously backed every Democratic nominee since 1996.

In a stunning rebuke, the International Brotherhood of Teamsters, one of the largest labor unions in the country, declined to endorse Vice President Kamala Harris in her campaign for president. While the union did not endorse Republican candidate former President Donald Trump either, a poll released by the Teamsters before their non-endorsement announcement showed nearly 60% of members asked supported Trump.

The lack of an endorsement was considered a “humiliating loss” for Harris and a victory for Trump. The Teamsters has endorsed the Democratic nominee for president every cycle since 1996, when they also declined to endorse a candidate.

Despite the rank-and-file support for Trump, labor activists criticized the lack of an endorsement, with former Teamsters President Jim Hoffa saying not endorsing Harris was a “critical error” on the part of Teamsters’ current leadership. The labor union’s current president Sean O’Brien shot back, saying the non-endorsement should cause Democrats to contemplate that “something’s wrong” with their standing and platform.

In the leadup to the union’s announcement, the meeting between union leadership and the Vice President was described as “tense.”

Democratic politicians are also attacking the Teamsters’ leadership. Congresswoman Alexandria Ocasio-Cortez blasted O’Brien, saying she’s been “very disappointed” in his leadership. O’Brien pushed back on Ocasio-Cortez, saying she should “focus on her job instead of mine.” O’Brien also accused Democrats of taking the Teamsters’ support for granted.

Some columnists argue the national union endorsement isn’t as significant as local endorsements, saying the “bonanza of endorsement from Teamsters units in the battleground states” are more important.

Others accused the Teamsters of factoring race into the equation. A former advisor to Illinois Democrat Sen. Dick Durbin said the union “won’t support a black woman” despite her supporting their “right to organize”, calling union leadership “a bunch of bigots.”

While the Teamsters declined to endorse Harris, she has gotten support from Hollywood celebrities such as Oprah, Meryl Streep, and Taylor Swift.