Stanley Rosenberg, facing disquiet over his domestic partner’s behavior as he prepares to assume the presidency of the state Senate next month, moved to shore up support Wednesday among colleagues by arguing that he has “enforced a firewall” between his legislative duties and his private life.
Rosenberg sent a letter to the other 33 Democratic senators after the Globe reported accusations that his partner, Bryon Hefner, had used social media to mock outgoing Senate President Therese Murray and had meddled in the internal workings of the Senate.
By late Wednesday, Rosenberg’s aides were convinced, after he aggressively moved to control political damage from the disclosures, that he is not losing support among Democratic lawmakers who tapped him to lead the chamber months ago.
“I’ve talked to a lot of members over the last day and even before that, knowing this was kind of kicking around, and everyone is committed to Stan and the direction he is going to provide the Senate,” said Senator Anthony Petruccelli, an East Boston Democrat.
“People are feeling comfortable,’’ said Senator Daniel Wolf, a Harwich Democrat. “Stan has handled this in a way that is consistent with what we know his leadership style will be.’’
Still, some Senate Democrats said privately that they harbored fears about potential damage to Rosenberg’s political footing if further revelations come to light.
Members also said they were concerned about encountering constituents whose first impressions of Rosenberg, given his to-date low public profile, would be rooted in controversy. Rosenberg’s ascendancy to the chamber’s top post is contingent on a vote of the entire membership.
The Globe reported Wednesday that Rosenberg had admonished Hefner and instructed him to stop talking with other senators about committee assignments, leadership positions, and staffing.
He has declined to comment on those reports.
What is at stake for Rosenberg, an Amherst legislator first elected to the Senate in 1991, is the formal selection of the next Senate president when the new legislative session convenes Jan. 8. Rosenberg is expected to be voted to the post by his fellow Democrats.
According to several Beacon Hill officials, he called senators Tuesday night to alert them to an “embarrassing” story to be published in the Globe. He also sent text messages early Wednesday morning to supportive senators offering them the chance to talk.
His damage-control effort was followed up with his delivery of a letter by midmorning to his fellow Democrats.
“As you saw from my response, I was open and transparent as I have been in the past,’’ he said of his interview with the newspaper. “I intend to lead the Senate in the same way.”
“As I have also told the Globe, I have enforced a firewall between my private life and the business of the Senate, and will continue to do so,’’ he wrote in his letter to his 33 Democratic colleagues.
The 65-year-old Rosenberg, now the Senate majority leader, outmaneuvered his rivals well over a year ago to win the Senate Democrats’ support to become the next president of the 40-member Senate.
Rosenberg said he ordered Hefner in June to shut down his social media postings after hearing complaints from Murray about disparaging tweets she believed came from Hefner.
One displayed a photo of Murray in a witch’s hat; another included a photo of what appeared to be an inebriated woman (not Murray) with a caption that suggested it represented the retiring Senate president.
Meanwhile, George Regan, a prominent Boston public relations executive, said he and his colleagues in the firm are “very embarrassed” by the Globe story and gave a clear warning to Hefner to dial back his erratic behavior.
He said Hefner, 27, whom he hired last May, promised not to act improperly in the future.
“We also recognize people make mistakes, us included, but I’m going to chalk this up to a horrible lesson for Bryon,’’ Regan said. “I take him at his word that it will never happen again.”
Regan also said he telephoned Murray to apologize to her for what she suspects are his employee’s derogatory social media postings aimed at her.
“I feel terrible,’’ said Regan. “I am very fond of Terry. She was very gracious.”