A clarification has been added to this story.

FOUR LEFT-LEANING UNIONS closely aligned with Boston Mayor Michelle Wu are directing money to a newly formed outside super PAC that is backing Boston City Council candidate Henry Santana, a former Wu aide who is considered a top hopeful for one of the four at-large seats in the November 7 election.

A mailer to voters from the unions’ super PAC highlights that Santana has Wu’s endorsement. As required by state law, the campaign flier, which began landing in mailboxes this week, also lists the top donors to the outside group calling itself Bold Boston: SEIU Local 32BJ, the Boston Teachers Union, SEIU 1199 and UNITE HERE. 

The unions, which represent teachers, hotel and health care employees, and property service workers, have a history of working with Wu.

The new super PAC emerged as another outside group, Forward Boston, backed by New Balance chairman Jim Davis, who opposed Wu in the 2021 mayoral election, is spending six figures to support conservative and moderate City Council candidates. 

Super PACs generally operate without fundraising or spending limits, but they cannot coordinate with the candidates they support. Super PACs have separate campaign accounts, and they are typically funded by wealthy individuals and unions.

Ben Martello, who runs a Lowell-based company that handles campaign finance compliance, filed paperwork on October 11 to create the Bold Boston super PAC, with the stated purpose of backing “candidates that have a bold vision for Boston.” Martello, whose client list includes Wu, declined to comment when reached by phone earlier this month. The word “bold” is one that Wu has often used on the campaign trail and inside City Hall in articulating her vision for transformative change.

Bold Boston hasn’t yet filed reports with campaign finance regulators detailing any fundraising or expenditures. The Santana mailer, a copy of which was reviewed by CommonWealth, is the first indication of its primary funders.

The Forward Boston super PAC, funded primarily by $300,000 from Davis, the New Balance chairman, is supporting at-large council candidates Bridget Nee-Walsh and Erin Murphy, District 6’s William King of West Roxbury, and District 3 candidate John FitzGerald in Dorchester. Davis has previously donated to Donald Trump at the federal level, and he was the primary backer of a separate anti-Wu super PAC during the 2021 mayoral race.

Forward Boston’s advertising spend was listed as going to Cape Cod-based Pierce-Cote, a PR firm owned by Regan Communications. George Regan’s firm sent out an email last summer touting an effort called “Save Our City,” characterized as a “3-year mission to save the City of Boston from the negative impacts of the ultra-progressive policies [that] dominate the current City Council and current administration at Boston City Hall.” Regan, a well-known Boston PR executive who served as press secretary to Boston Mayor Kevin White, later disavowed the email.

At the end of September, Forward Boston also pulled in a $10,000 donation from Thomas Kershaw, who owns Beacon Hill’s Hampshire House and the famous Cheers pub.

It wasn’t immediately clear whether the new union-backed super PAC will spend on other Wu-backed candidates besides Santana. 

The weeks leading up to the recent September preliminary saw a saw a surge in city workers and hotel union workers from UNITE HERE Local 26 joining the mayor on voters’ doorsteps to get out the vote for Enrique Pepen, another former Wu aide, who is vying for the district council seat representing Roslindale and Hyde Park.

Wu has also supported Councilor Ruthzee Louijeune, an at-large incumbent running for her second term, and endorsed Ben Weber, a liberal attorney who is running for the district seat representing Jamaica Plain and West Roxbury. (CLARIFICATION: Wu has held a fundraiser for Louijeune but has not formally endorsed her.)

Super PAC activity has been muted in Boston so far, compared with the millions of dollars spent during the 2021 mayoral election. Next week’s ballot is limited to the 13-member City Council, which has several incumbents running unopposed.

Nee-Walsh and Santana have lagged in fundraising, as the three incumbents – Murphy, Louijeune, and Julia Mejia – have each raised six figures. Santana has raised $60,000 so far, while Nee-Walsh pulled in roughly $53,000.

The Forward Boston super PAC recently also recorded spending nearly $5,000 on advertising for District 5 candidate Jose Ruiz, a retired Boston police officer who is running against Pepen, the former Wu aide. Pepen and Ruiz finished as the top two in the September preliminary, knocking out incumbent Ricardo Arroyo, a former Wu ally.

Ruiz has repeatedly said he is not interested in the super PAC’s help, as have District 3’s FitzGerald and District 6’s King.

Other unions involved in the fall election include South Boston-based Ironworkers Local 7, which is supporting Nee-Walsh, an ironworker who has described herself as right-of-center. The International Association of Fire Fighters, whose Local 718 is based in Dorchester, is also backing her, as well as Murphy.