Ernie Boch Jr., the auto magnate, invited about 80 friends over to his sprawling Norwood estate last week for a fund-raiser for Boston mayoral candidate John R. Connolly.
Less surprising than the campaign haul — about $40,000, Boch estimated — was the patron. Boch is a Republican.
Connolly is most definitely not.
But in the mayoral matchup against state Representative Martin J. Walsh, a leader in the labor community, Connolly is proving to be the preferred candidate of Republicans. Well-heeled GOP fund-raisers have been raising money for Connolly’s campaign, some citing their longstanding ties to Connolly’s parents, both Democrats who crossed the aisle to support Republicans.
Connolly’s mother was nominated for a judgeship by Republican governor William F. Weld and his father was appointed to the Boston Licensing Board by Republican governor Paul Cellucci. Connolly’s uncle, a lobbyist, was Cellucci’s top campaign fund-raiser.
His campaign has reaped support from those who worked in past Republican administrations on Beacon Hill, or who gave to the party’s 2010 nominee for governor, Charles D. Baker. He even picked up thousands in contributions from members of the board of the conservative Pioneer Institute, a think tank based on free market principles, individual liberty, and limited government.
To many Republicans, the division of support seems a logical outgrowth of the political duel now confronting Boston. While Connolly has championed the expansion of charter schools — a pet project of the Pioneer Institute — his opponent is best identified as a labor leader. Walsh, also a Democrat, headed the Boston Building Trades for years, only stepping down last spring to run for mayor.
Conservatives have cited Walsh’s background with foreboding. Last week, redmassgroup.com, a conservative Massachusetts blog, circulated a video showing Walsh leading a prolonged “union” chant at a 2011 rally showing solidarity with Wisconsin unions facing pressure from the governor.
Faced with that matchup, some small-government advocates are turning toward Connolly, the Democrat they find more palatable.
“Marty Walsh represents all that’s wrong with the system,” argued James Rappaport, a onetime chairman of the state GOP and 2002 candidate for lieutenant governor who is raising money for Connolly. “How he thinks he’ll honestly stand up to the major financial issues that are caused by generous arbitration and things of that ilk is beyond me.”
Connolly seized upon that theme last week, asking in a debate whose interests Walsh would serve if elected mayor. In an interview, a Walsh campaign aide pushed back, saying that Connolly should be held to the same standard.
“A week ago, John Connolly set the bar as to what money allegedly means,” said Walsh senior adviser Michael Goldman. “John Connolly ought to be judged by the people supporting his campaign.”
The Walsh campaign is happy to highlight Connolly’s Republican support, assuming it might prove a liability in liberal Boston. After winning the preliminary election, Walsh issued campaign signs that declare him a Democrat.
Goldman said they employed the word Democrat to emphasize the values it suggests.
“Even though he was running against another Democrat, we wanted people to know what Marty Walsh is — a progressive Democrat,” he said.
Boston has held nonpartisan elections since 1909, when it became one of the first cities to drop party affiliations in a push for government reform. Still, no Republican has occupied the mayor’s office since 1929 and few have even thrown a hat in the ring. Only 6.5 percent of registered city voters are Republicans.
The city is home, however, to notable Republican fund-raisers, including Rappaport and Chris Egan, a son of the late Richard Egan, the billionaire cofounder of EMC Corp.
Chris Egan has contributed to several Democrats in past years, but more reliably backs Republican candidates and causes. In 2012, he gave $10,000 to American Crossroads, the super PAC founded by President George W. Bush’s adviser Karl Rove. Egan did not return calls for comment.
In an interview, Connolly said, “Chris Egan’s a Boston resident raising kids in the city and it is a nonpartisan election.” He noted that he would not object to Egan “saying nice things about me.”
Connolly also collected $4,900 in contributions from 11 officers, board members, or spouses of board members at the Pioneer Institute. That list includes Ellen Roy Herzfelder, a former Romney administration official, and her husband, Bruce Herzfelder, a Republican candidate for treasurer in 2002, who live in Cohasset; and Brian J. Shortsleeve of Osterville, who served as political director for Romney’s 2002 campaign for governor . They did not return phone calls for comment.
Other notables who contributed to Connolly are Jason Kauppi, a former spokesman for acting governor Jane Swift; Thomas Trimarco, an unenrolled voter who served as Mitt Romney’s budget chief; Ann Murphy, a senior vice president at O’Neill and Associates who worked for Weld, Cellucci, and Romney’s 1994 US Senate campaign; and Gregg Lisciotti, a Leominster developer who has been active in fund-raising.
Added Matthew P. Keswick, who worked in three Republican administrations on Beacon Hill, “It’s no secret that John and I have known each other and I’ve been supportive of him and I’ve connected him with people that have supported him as well.”
Some Republicans have sided with Walsh, however. Walsh’s finance director, Kellie O’Neill, worked for the Weld and Cellucci administrations. Her husband, Stephen, was a close ally of Cellucci’s who served as his chief of staff and who also donated to Walsh. Walsh also picked up contributions from a big national GOP donor, John McDonnell Jr., of Florida, and his family, and longtime Cellucci ally Antonio Frias and his relatives, who work for Frias’s concrete company.
“John is a proud Democrat and in this nonpartisan election where there are two Democrats running, both John’s campaign and Representative Walsh’s campaign have received contributions from Democrats, independents, and Republicans,” said Connolly spokeswoman Natasha Perez.
Connolly’s parents had deep roots in the moderate Weld-Cellucci era, though they are Democrats. Lynda Connolly supported Weld for governor and he appointed her judge in 1997. The following year, Cellucci tapped Connolly’s father, Michael, a former secretary of state who supported his ticket, to head the Boston Licensing Board, even removing a Republican to give him the position.
Connolly’s uncle, James M. Connolly, was Cellucci’s campaign chairman, and his aunt, Paula, went to college with Cellucci’s wife, Jan, who gave to his campaign in September.
Some supporters said they gave to Connolly because of their shared history.
“I’ve known his family for a long time, through his dad,” said Rappaport. “Being from West Roxbury, I followed his career and thought he had done a great job with the education issue.”
Boch said he loves Connolly’s views on education and that he had known Connolly’s father for years. Michael Connolly produced a movie and shot some scenes in his house, he noted.
“There’s great lineage there and I’m very excited. I hope John Connolly wins,” Boch said.
Asked about his support in Republican circles, Connolly said: “I’m happy for all the support I get in Boston. I’m very clear about where I stand on the issues and what my vision for Boston is.”
Is Connolly going to issue new signs affirming that he, too, is a Democrat? “I don’t have the resources to go and reprint a whole bunch of signs,” he said.Stephanie Ebbert can be reached at Stephanie.Ebbert @globe.com. Follow her on Twitter @StephanieEbbert