A union whose members booed Republican vice presidential candidate JD Vance in August refused to endorse the Harris campaign on Thursday.

'This decision, which we take very seriously, is the best way to preserve and strengthen our unity.'

The International Association of Fire Fighters released a statement Thursday saying they would not endorse a presidential candidate despite being the first union in 2020 to eagerly endorse Joe Biden's campaign.

"Over the past year, the IAFF took unprecedented steps to hear our members' views on the candidates and the policy issues that matter most to them," said union general president Edward Kelly. "This decision, which we take very seriously, is the best way to preserve and strengthen our unity."

The announcement is seen as a monumental victory for the Republican Trump-Vance campaign, which has made a concerted effort to steal away support of unions from Democrats to the Republican column.

Many on social media noted that the Harris campaign had mocked Vance for getting booed by some members of the IAFF union. A tweet in August with video of the incident garnered more than 2.5 million views.

The International Brotherhood of Teamsters made a similar decision in September to refuse to endorse a presidential candidate after the union president spoke at the Republican National Convention. Democrats excoriated the union president, no doubt due to polling that showed union members were breaking for Trump away from Democrats.

"We encourage our members — and all eligible voters — to get out and make their voices heard in the upcoming election," Kelly concluded.

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