Boston Mayor Marty Walsh speaks at a press conference announcing the postponement of the Boston Marathon to September 15th on March 13, 2020 in Boston, Massachusetts. (Photo by Scott Eisen/Getty Images)
CNN  — 

President-elect Joe Biden is expected to tap Boston Mayor Marty Walsh as labor secretary, two sources familiar with the decision tell CNN.

Walsh is a veteran union operative, eventually rising to lead Boston’s Building and Construction Trades Council, a group that represents ironworker and electrician unions, among others. He outlasted California Labor Secretary Julie Su, who was believed to be among the finalists and Michigan Rep. Andy Levin, who had support from major unions. Vermont independent Sen. Bernie Sanders had also sought the support of labor leaders, but was largely rebuffed.

The decision to select Walsh, which was first reported by Politico, is a victory for AFL-CIO President Richard Trumka, who rallied his federation of 56 unions to back the Boston mayor soon after Biden won the election in November.

By taking the job, Walsh would sidestep a potentially difficult re-election campaign – one he had not yet committed to running – in Boston, with City Councilors Michelle Wu and Andrea Campbell already launching bids. Walsh’s selection could meet some backlash from progressives, who favored Su or Levin, whose path was complicated by the thin House Democratic majority.

“As a longtime union member, Walsh knows that collective bargaining is essential to building back better by combating inequality, beating COVID-19 and expanding opportunities for immigrants, women and people of color,” Trumka said in a statement. “He will have the ear of the White House, the Cabinet and Congress as we work to increase union density and create a stronger, fairer America.”

Walsh first joined the Laborers’ Union Local 223 at age 21. By 2011, he had risen to lead the Boston Trades Council.

But his nomination could expose some faultlines in the labor movement, particularly on questions of climate policy and diversity, that were largely set aside during Biden’s campaign to defeat Trump. Levin had the support of unions like the Communications Workers of America and United Auto Workers. And Su would have been among the highest ranking Asian American officials in the administration if she were selected.

Walsh and Biden also have a longstanding relationship. When Walsh won Boston’s mayoral race in 2013, the then-vice president called Walsh to congratulate him (but first spoke with the wrong Marty Walsh). Walsh was also a rumored potential Labor pick in 2016 had Hillary Clinton won the presidency.

Biden is shoring up his Cabinet amid a crisis in Washington, where a pro-Trump mob laid siege to the US Capitol on Wednesday in a deadly riot incited by the President.

Biden also expected to tap Rhode Island Gov. Gina Raimondo as commerce secretary, two people familiar with the matter say, in a round of formal announcements on Friday. The President-elect is also poised to nominate Isabel Guzman to lead the Small Business Administration, two sources said.

Biden sees the three jobs CNN has confirmed Thursday – commerce secretary, small business administrator and labor secretary – as a trio that will work together, a source familiar with the decision said, focused on the economic crisis caused by the coronavirus and how to combat economic inequality.

The three nominees will be announced as a group on Friday, the source said.

This story has been updated.