Charlotte Golar Richie called state Representative Martin J. Walsh Friday to tell him she would endorse his campaign for mayor, three people with direct knowledge of the call said.
The decision by Golar Richie, who finished third in the Sept. 24 preliminary election, potentially gives Walsh a significant boost in building vital support in the African-American community.
“Charlotte believes that Marty understands the struggles of working people, because he has lived through it,” said one of the people, who spoke to Golar Richie after the call. “She knows that he will stand up for the people who have been marginalized and disenfranchised, because those people are his neighbors.”
Golar Richie received almost 14 percent of the vote in the preliminary election, and her backing had been heavily courted by Walsh and his opponent, Councilor at Large John R. Connolly. She made her decision Friday evening, said people with knowledge of the choice. Those individuals spoke on the condition of anonymity.
Golar Richie issued a press release saying she would announce her endorsement at 10 a.m. Saturday at First Parish Church, a few blocks from her home in Dorchester. Golar Richie and Walsh did not respond to phone messages seeking comment.
A Connolly spokeswoman said that he understood that Walsh and Golar Richie have known each other for 20 years from Dorchester and their time in the Legislature.
“While it would have been nice to receive Charlotte’s endorsement, we continue to focus on talking to voters, sharing our vision, and getting their vote on Election Day,” said the spokeswoman, Natasha Perez.
For Connolly, there was some good news. Several key people from Golar Richie’s campaign split with the candidate and will join Connolly, including her field director Darryl Smith, a veteran of Mayor Thomas M. Menino’s political operation, and her finance chairman, Clayton Turnbull.
“I think after assessing Marty Walsh’s and John Connolly’s strengths, we think that John Connolly is going to be the most effective leader in moving our neighborhood forward economically and when it comes to education,” Turnbull said Friday. “We think that education, the economy, and the conditions of our neighborhoods are a three-legged stool.”
Connolly also has received the endorsement of several black ministers. But with Golar Richie’s decision, Walsh has won the backing of the three most prominent candidates of color in September’s preliminary election for mayor.
Earlier this week, Walsh was endorsed by former nonprofit executive John F. Barros, who is of Cape Verdean descent, and Councilor at Large Felix G. Arroyo, whose parents came from Puerto Rico. Arroyo finished fifth, and Barros placed sixth in the preliminary election among 12 mayoral candidates.
The three endorsements could be crucial in a contest between two white men in an increasingly diverse city. Walsh and Connolly advanced to the final election with strong showings in predominantly white sections of the city. To win Nov. 5, the candidates must make inroads in communities of color.
Two recent polls have shown Connolly leading Walsh by 7 and 8 percentage points.
Golar Richie grew up in Brooklyn, but has deep roots in Dorchester, where she has lived on Meeting House Hill for 26 years. She served in the Legislature in the 1990s, but left to become Boston’s chief of housing under Menino. She also worked as a top aide to Governor Deval Patrick.
Golar Richie was the last major candidate to jump into the mayoral race this spring. She had been out of government for several years and began the race with no money, which proved to be a significant disadvantage. But she was the only woman on the ballot with 11 men and outperformed several other candidates with larger war chests.
In the preliminary election, Walsh topped the ticket with 20,854 votes. Connolly received 1,419 fewer votes and took second. Golar Richie finished third and missed advancing to the final by 3,889 votes.
On the surface, Golar Richie and Walsh have more in common. They live a mile from each other and both served in the Legislature, overlapping at the State House for some time.