Team of Rivals: John Barros, left, and City Councillor Felix Arroyo, right, endorsed State Rep. Marty Walsh’s candidacy for mayor of Boston during a press conference in Egleston Square on Tuesday morning. Photo by Paul Marotta

State Rep. Marty Walsh this week picked up the support of two former rivals and a Democratic ward committee in his pursuit of the mayor’s office while City Councillor At-Large John Connolly received backing from East Boston Councillor Sal LaMattina, one of Walsh’s State House colleagues, and a ward committee.

On Tuesday, Walsh locked hands with City Councillor At-Large Felix Arroyo and former School Committee member John Barros and raised them high as the three politicians stood united in front of a bank of television cameras, “Martin Walsh for Mayor” stickers on their lapels, in a small park in Egleston Square. Because of their status and influence in communities of color, the Arroyo and Barros endorsements were eagerly sought after by both mayoral finalists. In the preliminary, Arroyo came in fifth, with 8.77 percent of the vote, while Barros received 8.1 percent, placing sixth.

In the days after the Sept. 24 primary, Arroyo and Walsh met at Walsh’s home on Tuttle Street at 10:30 p.m. after the state lawmaker had finished a day of campaigning. Arroyo had policy papers from his mayoral campaign in hand, and he and Walsh sat on the back porch for two hours.

“That was very impressive to me,” recalled Arroyo, who said he initially spoke with both candidates but Walsh then offered to meet at his home.

Barros, an Uphams Corner resident who stepped down from both his School Committee post and his job as executive director of a local nonprofit to run for mayor, said that Walsh’s “vision” was similar to his. After he had sat down with Connolly at the Haley House in Roxbury, Barros said he then spoke with Walsh, a longtime labor leader, about increasing the number of minorities and women on Boston construction sites as well as the number of black and Latino contractors who are not members of a union.

“Marty is the right candidate for making sure all of Boston participates in our economy,” Barros said.

Asked if he and Walsh had spoken about a position for him in a potential Walsh administration, Barros said they had not.

“Felix walked in with his papers, I walked in with my thing, my policy.”

Walsh also received the backing of the Ward 15 (Meetinghouse Hill, Bowdoin-Geneva, and parts of Fields Corner) Democratic Committee on Sunday.

For his part, Connolly rolled out his own endorsements yesterday, from state Rep. Aaron Michlewitz, a North End Democrat, District 1 City Councillor Sal LaMattina of East Boston, and the Ward 4 Democratic Committee, which is based in the South End. Michlewitz and Ward 4 Democrats had backed former state Rep. Charlotte Golar Richie in the preliminary. Golar Richie, who came in third in the preliminary, has not yet said who, if anyone, she would endorse.

Communities United, a small group of community activists that includes William Celester and Leonard Lee, said in an e-mail earlier this week that they would announce their endorsement of Connolly in the South End’s Villa Victoria on Thursday afternoon.

While Arroyo and Barros were announcing their backing for Team Walsh in Jamaica Plain, Connolly, the chair of the City Council’s education committee, was testifying at the State House in support of a drop-out prevention bill.

The proposal, filed by state Sen. Sonia Chang-Diaz, calls for graduation coaches in high schools and raises the mandatory school attendance age to 18 from 16 years old. According to Connolly, 1,146 students dropped out of Boston schools last year, and drop-outs are statistically likely to end up in jail and unemployed, or having children of their own early.

“These three outcomes – higher crime and incarceration rates, persistent poverty, and strong correlation with teen pregnancy – mean that when a young person drops out of school, it can create harmful ripple effects across a family, a neighborhood, a city, and beyond,” the candidate said.