By Nandita Bose
WASHINGTON (Reuters) -The International Association of Fire Fighters on Thursday said it would not make a presidential endorsement, in what was widely viewed as a blow to Vice President Kamala Harris' campaign to stay in the White House.
The union, which represents 300,000 career firefighters and emergency responders, determined "by a margin of 1.2%" against picking a candidate, General President Edward Kelly said in a statement.
"This decision, which we took very seriously, is the best way to preserve and strengthen our unity," Kelly said.
The decision is a setback for the Harris campaign, which is relying on organized labor to boost its outreach to working-class voters, particularly in the key swing states of Wisconsin, Pennsylvania and Michigan.
It is also notable because the union was the first to endorse Democrat Joe Biden at the outset of his successful challenge to Republican then-President Donald Trump in 2019.
The Harris campaign did not respond to a request for comment. The Trump campaign called it "another devastating blow to Kamala Harris' failing campaign."
The firefighters decision comes two weeks after the International Brotherhood of Teamsters, one of the nation's largest unions, announced it would not endorse a candidate in the presidential race this year. Harris has, however, 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 organized labor groups since she replaced Biden on the Democratic ticket, including the United Auto Workers and the AFL-CIO union federation.
Harris has pledged to carry on with many of the same labor 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. The union had backed away from endorsing Hillary Clinton in 2015.
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 (NASDAQ:JD) Vance speaking at the event.
Harris also addressed a separate IAFF legislative conference in Washington, D.C., in March, before Biden dropped out of the race.