State Representative Martin J. Walsh’s mayoral campaign, which has racked up a string of endorsements from politicians of color, is expected to add four more members of the Boston delegation to his roster of supporters, according to people familiar with the pending announcement.

State Senator Sonia Chang-Diaz of Jamaica Plain, City Councilor Tito Jackson of Grove Hall, and state representatives Russell Holmes of Mattapan and Carlos Henriquez of Dorchester will endorse Walsh as early as Friday, the people with knowledge of the decision said.

The expected quadruple endorsement comes on the heels of Wednesday’s announcement by state Senator Linda Dorcena Forry that she would support Walsh, and last week’s endorsements from City Councilor Felix G. Arroyo, nonprofit executive John F. Barros, and Charlotte Golar Richie, who finished third in the September mayoral preliminary election.

Advertisement - Continue Reading Below

City Councilor John R. Connolly, Walsh’s rival, last week trumpeted support from more than a dozen black clergy members.

Both candidates have been vying for support from voters of color and powerbrokers within those communities, having collected the vast majority of their support in the Sept. 24 preliminary election from white voters.