U.S. Sen. Scott Brown (R-Wrentham) is milking former Mayor Ray Flynn’s endorsement for all its worth. But how much it’s worth is an open question. Flynn, a registered Democrat from South Boston and former US ambassador to the Vatican, joined Brown at Adams Corner’s Irish Heritage Festival last October, a fact noted on Brown’s public schedule. Flynn has said he voted for Brown in the special 2010 election to replace the late US Sen. Edward Kennedy.

Then in the thick of the debate over whether a Senate amendment protected religious liberty or cut into a woman’s right to choose, Flynn wrote a letter of support for Brown, who backed the amendment.

And this week Flynn stood with Brown on Castle Island to announce his formal endorsement. Flynn’s backing was tied to an endorsement from another former Democratic mayor of a large city, Worcester’s Konnie Lukes.

Brown has been reaching out to conservative Democrats in his campaign to keep his seat as he faces a challenge from consumer advocate Elizabeth Warren, a Cambridge Democrat. The trips to Castle Island Park in Southie and Worcester, two blue collar areas and home to the former mayors, underscore that point.

As to the impact of the Flynn endorsement for Brown outside the Eire Pub, only time will tell. Earlier in April, Peter Ubertaccio noted on the “Mass. Political Profs” blog that Flynn has not held public office since he left for the ambassadorship, and that he came in second place in a run for Congress, behind Michael Capuano, a Somerville Democrat. In last year’s District 3 City Council race, Flynn backed Frank Baker, a Democrat who admires Franklin D. Roosevelt, but it was an endorsement that probably did not significantly move the needle for voters who had already made up their minds.

“And yet, Flynn might be able to aid Brown in the areas where he’ll need the most help: the urban, conservative cities where Brown must pick up enough votes to hold Warren to a close margin,” Ubertaccio wrote.

Which is probably why, after Brown’s latest blarings of Flynn’s support, the Massachusetts Democratic Party sent out a release blasting Flynn and Lukes as “part of a group of Massachusetts political leaders who register as Democrats but regularly support Republican candidates and Republican policies.”

A party spokesman ticked through several news and blog clips: Flynn endorsing Mitt Romney for president; Flynn and Lukes backing Paul Cellucci, a GOP candidate for Massachusetts governor; and Lukes declining to attend an event with President Bill Clinton in 1998 in reaction to the Monica Lewinsky scandal.

This is, of course, a move into dangerous territory, intimating who can be and who can’t be called a true blue Democrat, and steps away from a Party Purity Police force. (Republicans have their own Purity Police; Brown was slammed on Twitter and Facebook as a “Republican-In-Name-Only” after he voted to break a Republican filibuster on a jobs bill in February 2010.)

More than a few Democrats in Congress, particularly those facing a tough re-election in 1998, were willing to censure Clinton to show they didn’t approve of his behavior.

Locally, a look at the Boston Phoenix’s archives reveals the names of two dozen elected officials who called themselves “Democrats for Cellucci.” The article also noted it “didn’t hurt that Democratic powerhouses like House Speaker Tom Finneran and Boston Mayor Tom Menino didn’t support [Democratic nominee Scott] Harshbarger enthusiastically and rarely protested when they were portrayed as preferring Cellucci.”

Menino, by the way, has called Brown tough to beat several times, though this week he said Warren appeared to be working hard on the campaign trail.

A Democratic Party press release detailing Menino’s rifts with various Democrats – and there have been several – is unlikely to hit reporters’ inboxes any time soon.

Arroyo chief of staff headed to Wisconsin for Senate campaign
A top aide to City Councillor At-Large Felix Arroyo is en route to Wisconsin to work on a US Senate race. Stuart Rosenberg was a campaign adviser during Arroyo’s first City Council run in 2009 and has since worked as his chief of staff. He previously worked on former state Sen. Jarrett Barrios’s run for Middlesex district attorney, managed state Rep. Linda Dorcena Forry (D-Dorchester) ’05 victory, and headed up District 8 Councillor Michael Ross’ office.

Rosenberg will be working on Tammy Baldwin’s Senate campaign as field director, starting Monday. Baldwin, an openly gay Democrat who has served in Congress and already won the endorsement from her party, will face off against one of four Republicans competing for the nomination. The roster includes former Gov. Tommy Thompson. The seat opened up with the retirement of Democratic U.S. Sen. Herb Kohl.

Arroyo called Rosenberg a friend and a “valuable resource” to constituents. “We’ll miss him,” he told the Reporter.

Menino: Re-election call in the ‘next several months’
Mayor Menino said he’ll be making a decision on whether to run for another four-year term in 2013 in the “next several months.” Menino made the comments to WCVB-TV’s Janet Wu and Ed Harding, the hosts of “On The Record,” a political chat show airing on Sunday mornings.

“I have to decide: Am I still making a difference in the city of Boston,” said Menino, who has held the mayoralty since 1993. Political observers inside and outside City Hall believe Menino will launch another campaign.

“I can probably get reelected without really working hard at it,” Menino told Harding and Wu. “But I just say, I want to make a difference.” In the interview, Harding noted that Menino will be 70 years old in December.

“My consideration is how much more can Angela take,” Menino said, referring to his wife. “That’s the real issue. How much more she can take? She’s a saint.”

No serious challengers have made noises about running for mayor next year. Will Dorcena, who ran unsuccessfully for a City Council At-Large seat last year, announced his mayoral run in January. On his Facebook page, he claimed to be the first candidate out of the gate, but that designation belongs to TOUCH 106.1 FM’s Charles Clemons, who said he was running for mayor in 2011. Clemons is a co-founder of the Grove Hall-based radio station.

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