PITTSBURGH — Joe Biden officially earned the endorsement of the firefighters union Monday, putting in his corner a powerful organizing force that stayed on the sidelines of the 2016 race.

The executive board of the International Association of Firefighters met and voted to ratify its endorsement of the former vice president within hours of his formal entry into the race on Thursday. The union had warmly welcomed Biden to their annual Washington convention last month with signs of “Run, Joe, Run!”

General President Harold Schaitberger made the endorsement official in an online video.

“Joe’s a lot like our firefighters. He's a problem solver who cares deeply about America, and [is] committed to making our country better,” Schaitberger says. 

Schaitberger and other firefighters union members will join Biden as he holds his first public campaign event Monday in a city closely associated with then union movement, Pittsburgh. Biden is expected to focus his remarks at a Teamsters Union hall on his plans to rebuild the middle class, calling it the “backbone” of American society.

The IAFF video focused on his economic appeal.

“He’s one of the staunchest advocates for working families. He knows that a strong middle class means a strong America. And we know as president he will stand up for all the patriotic Americans who want nothing more than to earn a decent wage, send their kids to college, have affordable healthcare and a decent and secure retirement,” Schaitberger said in the video. 

The IAFF stayed out of the 2016 election, declining to endorse Hillary Clinton in her bid against Donald Trump. IAFF endorsed Chris Dodd in the 2008 Democratic primary despite Biden’s presence in the field then. It’s backing of John Kerry in 2004 helped the then-Massachusetts senator emerge as the nominee.