Michael Sullivan expected to enter Massachusetts GOP Senate primary

Former U.S. Attorney Michael Sullivan is expected to announce his campaign for the Massachusetts GOP Senate nomination Thursday, according to a Bay State Republican insider.

Sullivan is expected to join state representative Dan Winslow and businessman and former Navy SEAL Gabriel Gomez in the Republican primary for John Kerry’s vacated U.S. Senate seat, which will be filled by a special election on June 25.

Ever since newly minted Fox News contributor Scott Brown opted out of the race, the Republican primary has been wide open. Two-time congressional candidate Sean Bielat has also picked up signature papers for a potential run.

Sullivan is a former acting director of the Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF) in the Bush administration. Sullivan’s nomination to become permanent ATF director was blocked by three Republican senators on the grounds that Sullivan showed no willingness to reverse the ATF’s tough stance on small gun dealers.

Democratic congressman Ed Markey, the heavy front-runner in the race, is facing a primary challenge from underdog Democratic congressman Stephen Lynch. Both Democratic candidates have already faced behind-the-scenes criticism from Massachusetts political insiders.

Lynch recently changed from a pro-life to a pro-choice stance, presumably to improve his electoral odds in the statewide election. Markey, meanwhile, has been quietly mocked for branding his campaign volunteers “Markey Fellows,” a sign that┬áRepublicans plan to paint him as an elitist.

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