With housing at center of Boston mayor’s race, labor and developers are organizing to push candidates

The carpenters union wants to send a message that development is good — for workers and the city as a whole.Lane Turner/Globe Staff

A group of pro-development forces, led by one of Boston’s biggest construction unions, is marshaling resources and at least $500,000 to try to influence the mayoral race, in which housing has emerged as a major issue with little consensus on how to tackle it.

Notably, the Responsible Development Coalition, as the group calls itself, is not immediately endorsing a candidate in the six-way race, and may never. Instead, the Dorchester-based North Atlantic States Regional Council of Carpenters and its developer partners have formed the coalition to launch a slate of television, radio, and digital ads urging candidates to sign a pledge to support “responsible real estate development . . . crucial to our future, our economy and collective quality of life.”

The group’s formation underscores a sea change from the last open mayoral race, in 2013, when labor groups largely coalesced around Martin J. Walsh, a former head of the Building and Construction Trades Council, in his successful campaign. Over the next seven years, Walsh retained the loyalty of construction unions while also winning broad support from developers as he oversaw the construction of 30,000 new units of housing and millions of square feet in office and lab space.

Still, rents and home prices here remain among the highest in the nation. Big projects are changing the look and feel of many city neighborhoods and there’s growing concern that the ongoing surge in construction is displacing or pricing out middle- and working-class Bostonians.

Many recent polls — including one commissioned by the Responsible Development Coalition — place housing at or near the top of the list of concerns Boston residents want the new mayor to address.

Precisely how, though, remains up in the air, with developers, construction interests, tenant groups, and a wide range of others seeking to influence the debate.

Joe Byrne, executive secretary-treasurer of the 30,000-member carpenters union, hopes candidates will support good wages and working standards, affordable housing, and “robust” community dialogue about development. Some of these are traditional union priorities, while others are issues virtually every candidate has said they support.

Generally, Byrne said, the group wants to send a message that development is good for Boston — for workers and the city as a whole.

“Thousands of our members work here and live here and our future is directly tied to the future of Boston and the next mayor,” he said. “This is a critical race for us. We have a lot on the line.”

With three months until the September preliminary election, no candidate has emerged as a clear-cut favorite of the development community, construction unions, or housing advocates. A few trade unions have endorsed specific candidates, but many of the city’s powerful interests are continuing to feel out the field or simply spread donations throughout it, hedging their bets.

The new coalition is putting big money behind the broad, pro-development agenda. The carpenters union alone will commit hundreds of thousands of dollars to the effort, Byrne said, with more coming from two development firms that have also signed on. RISE Construction, a self-described “middle market” developer founded by former Suffolk executive Jim Grossmann, and Intercontinental Real Estate Corp. CEO Peter Palandjian have each committed $100,000, and the union is talking with other builders about joining the effort, which will formally launch Wednesday.

“This isn’t, ‘Are you pro-development or not pro-development?’ Most people get that for a city to thrive, from a revenue perspective, development is helpful,” Grossmann said. “What we’re searching for is, what does that look like?”

“Marty [Walsh] was a construction person. We all knew he could be good for development. For this, I don’t think anyone is bad for development,” Grossmann said. “But business thrives on clarity.”

The coalition is also planning to run the ads starting this month, said Chris Keohan, a political consultant working with the group. It also has funded its own polling that identified housing, and more specifically affordable housing, as the leading issue among 400 likely voters surveyed in mid-May by Global Strategy Group, a public relations firm.

That poll, like other public surveys, found that most voters — 31 percent — were still undecided about who they will vote for, with Acting Mayor Kim Janey and City Councilor Michelle Wu atop the field.

Wu has staked out some of the most progressive stances on housing, and at a forum last week was the lone candidate to say she’d support rent control — which Massachusetts voters banned in 1994 but some on Beacon Hill have pushed to allow again. This week, Wu has planned a series of housing-related events in a bid to put a spotlight on the issue.

As the city’s chief executive, Janey has broad powers to influence housing and development policy, and last week expanded a program for first-time homebuyers to offer aid of up to $40,000 — more than triple the previous amount. The development community has closely watched Janey for clues on how she views large projects around the city, but so far she has offered few.

Among the other candidates, City Councilor Andrea Campbell has issued a detailed plan that includes “reimagining” the Boston Planning & Development Agency to strengthen its planning function, and refining affordable housing requirements to better match the incomes of city residents. John Barros, the city’s former economic development chief, says he’d increase new development if elected, to expand supply while continuing to add new affordable units.

City Councilor Annissa Essaibi George has said she would boost funding for public housing and to prevent evictions. And state Representative Jon Santiago says he would issue city bonds to fund more affordable housing and reform the city’s arcane zoning code.

The fledgling development coalition may never actually pick a horse in the race; members have relationships with many of the candidates. But the carpenters union — which has a deep war chest and thousands of members who live in Boston — likely will endorse, Byrne said.

“But right now the field is pretty open,” he said. “We’re going to make the call when the timing is right.”