The International Association of Fire Fighters (IAFF) announced Thursday that it would not be making a presidential endorsement, marking a significant setback for United States Vice President Kamala Harris.
The union's General President Edward Kelly announced that the union has decided to endorse neither Harris or her Republican rival Donald Trump in this year's presidential elections in November.
In his statement, Kelly said that the union, which represents 300,000 career firefighters and emergency responders, made the decision "by a margin of 1.2%".
"This decision, which we took very seriously, is the best way to preserve and strengthen our unity," said Kelly.
The union's decision poses a challenge for the Harris campaign, as it has been counting on support from organised labour to strengthen its appeal to working-class voters, especially in the key swing states of Wisconsin, Pennsylvania and Michigan, Reuters reported.
While the Harris campaign silently sulks at the union's decision, the Trump campaign decided to take a dig at their rivals over the development, calling the "another devastating blow to Kamala Harris' failing campaign."
In 2019, the union was the first to endorse Democrat Joe Biden at the outset of his successful challenge to Republican then-president Trump.
This decision comes two weeks after the International Brotherhood of Teamsters, one of the nation's largest unions, also announced it would not endorse a candidate in the presidential race this year.
However, Harris has racked up regional endorsements around the country from Teamsters locals, who represent over a million workers.
The vice president has also earned the support of several other major organised labour groups since she replaced Biden on the Democratic ticket, including the United Auto Workers (UAW) and the American Federation of Labor and Congress of Industrial Organizations (AFI-CIO) union federation.
Harris has pledged to carry on with many of the same labour policies as Biden, who often touts himself as the most pro-union president in history.
Some senior Harris campaign officials, academics and Democrats have tied the decision to not endorse Harris to a reluctance in accepting women in key leadership roles.
Both presidential campaigns made personal appeals to the firefighters union's members in August, with Harris' running mate Tim Walz and Trump's running mate JD Vance speaking at the event.
Harris also addressed a separate IAFF legislative conference in Washington, DC, in March, before Biden dropped out of the race.
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