In a video released Monday, The International Association of Fire Fighters officially endorsed former Vice President Joe Biden for president, becoming the first key labor group to endorse a candidate in the 2020 election.
Watch below:
Biden expressed gratitude for the endorsement and pledged to "fight to strengthen [unions] and grow the backbones of this country."
It wasn't long before President Donald Trump railed against Biden and the "Dues Sucking" leadership of the International Association of Fire Fighters.
Biden soon responded after his Pennsylvania rally.
Trump won Pennsylvania's 20 key electoral college votes in the 2016 election, but skepticism is growing on whether or not he can clench the battleground state in the upcoming presidential election.
If the president keeps railing against unions, it doesn't appear he'll win over a lot of potential supporters.
Trump may have some fires of his own to put out after this latest rant.