Four years after Teamsters Local 25 threw its weight behind Democrat Martha Coakley in her race for governor against Gov. Charlie Baker, the union has come around on the Republican governor, endorsing Baker's bid for re-election.

The Charlestown-based union, which represents 11,500 workers and is the largest Teamsters union in New England, called Baker the strongest candidate in the race to strengthen the economy and create new jobs.

"Charlie Baker is a proven leader who has rolled up his sleeves and worked hard to improve our state," Teamsters Local 25 President Sean O’Brien said in a statement. "In today's economy where corporations are relocating and downsizing to save money, it is more important than ever to elect a candidate who will leverage our state's competitive advantage to protect jobs and attract new businesses."

The endorsement is based on Baker's past work - while he's running for re-election the governor has not outlined his case for another four-year term.

The union pointed out Baker's efforts to improve training opportunities for workers in growing fields in Massachusetts, his willingness to work with labor leaders and what it called "leadership on critical economic development and infrastructure issues."

In backing Baker, the union has shunned three Democrats running for governor in a state where the Democratic Party has traditionally been able to count on labor's support and organizational strengths to win campaigns.

Teamster Local 25 twice backed the Democratic ticket over Baker, siding with incumbent Gov. Deval Patrick and Lt. Gov. Timothy Murray in 2010 in a race that Baker lost.

"Teamsters Local 25 is proud to endorse Charlie Baker. He is a leader who consistently puts politics aside, reaches across the aisle and will work with anyone who shares his goal of putting people first," O'Brien said.

In December, Teamsters Local 25 of Boston endorsed Democrat Lori Trahan of Westford in her bid to succeed Congresswoman Niki Tsongas of Lowell.