A pro-Deval Patrick super PAC raised almost $350,000. Most of it came from one person

Deval Patrick.SUZANNE KREITER/GLOBE STAFF/FILE 2015

In mere weeks, a pro-Deval Patrick super PAC raked in nearly $350,000 in contributions, flexing that type of fund-raising muscle for which the former governor himself is known. It can thank a single donor for most of it.

Dan Fireman, the managing partner of a Waltham private equity firm, donated $250,000 to the Reason to Believe PAC, accounting for the biggest chunk of cash among the dozens of donations it raised over a month, according to its most recent financial filing.

Fireman, who founded Fireman Capital Partners, is a reliable Democratic donor who’s given $20,000 to the Democratic State Committee since 2009 and, four years ago, poured $12,500 into the Mass. Independent Expenditure Political Action Committee, a now-defunct PAC that spent millions of dollars opposing Governor Charlie Baker’s 2014 gubernatorial campaign.

Fireman’s connections to the PAC don’t stop at donations, though: Doug Rubin, a former Patrick aide who helped launch the committee in August, is also listed as an operating partner at Fireman’s firm.

Rubin said he and Fireman have been friends since he was young — he said his father was friendly with Fireman’s dad, former Reebok CEO Paul Fireman — and that Fireman’s motivation for donating goes beyond them working together.

“He cares about a lot of the same progressive issues that we all do at the PAC,” Rubin said. “He understands it’s a really important midterm election.”

Fireman declined to comment on his donations Monday.

The PAC, named for Patrick’s 2011 autobiography, was created by John Walsh and Rubin, who has said Patrick wouldn’t be involved in its activities supporting Democrats across the country. Still, it has helped stoke speculation about the political future of Patrick, who has said a 2020 presidential run is on his “radar screen.”

Beyond Fireman’s donations, the PAC tapped into the state’s well-worn fund-raising circles, getting donations from John Fish, the chairman and chief executive of Suffolk Construction, who contributed $50,000, and dozens of others with Massachusetts addresses.

The PAC spent $17,600 in its first month, including $10,000 to Rubin’s own political firm, Northwind Strategies, and has begun rolling out endorsements in various states, including of six congressional candidates Tuesday in Kansas, New Mexico, North Carolina, Tennessee, and New Jersey.

“We’ve done a number of canvasses,” Rubin said. “We’ve brought volunteers into districts. We’re really focused on the grass-roots piece.”