Standing before the State House steps and a thicket of supporters wielding blue campaign signs Wednesday afternoon, Sciortino cast himself as the most liberal candidate in the race.
“As Governor Patrick said last year, we need Democrats with a backbone,” he said.
Sciortino, 34, is one of at least five Democrats gearing up for a run.
State Sens. William Brownsberger of Belmont, Katherine Clark of Melrose and Karen Spilka of Ashland have all said they will run. Middlesex County Sheriff Peter Koutoujian has also declared his interest in the race.
Former state Sen. Warren Tolman says he is weighing a candidacy.
In a wide open race, early attention has focused on the candidates’ geographic power bases and interest group appeal.
Clark has made substantial inroads with women’s advocacy groups. Spilka has the support of AFL-CIO officials in the western part of the district. And Koutoujian is expected to draw substantial support from law enforcement groups.
But Sciortino, who is openly gay, sought to transcend those allegiances Wednesday with a broad appeal to the party’s liberal base.
“This race is not going to be about who the women’s candidate is or who the gay candidate is, the law-and-order candidate,” he said. “It’s going to be about who will be the progressive Democratic leader, who has always been there for us and always will be.”
Sciortino, of Medford, went on to trumpet his support for a host of liberal causes: vowing to fight for privacy in an age of government surveillance, for instance, and saying he would push to overturn the Supreme Court’s Citizens United decision, which opened the door to unlimited spending by corporations and unions on political campaigns.
On the day the Supreme Court overturned the Defense of Marriage Act, clearing the way for federal recognition of same-sex nuptials, Sciortino choked up acknowledging his fiance, Pem Brown, in the crowd.
The pair are set to marry in October.
Sciortino first ran for state representative at age 25, ousting an incumbent who backed a ban on gay marriage.
Since then, he has developed a reputation as a committed liberal willing to buck the legislative leadership.
Last summer, when the House of Representatives voted 135-19 to pass a controversial bill designed to prevent illegal immigrants from registering vehicles, Sciortino was one of the handful of dissenters.
And in his announcement speech Wednesday, Sciortino said he was the only candidate in the race who “enthusiastically supported” Patrick’s ambitious budget proposal earlier this year.
The governor called for a $1.9 billion tax hike to fund what Sciortino called “generational” investments in transportation and education. Legislative leaders balked at the plan and coalesced behind a smaller tax-and-spend package.
The revenue side of that more restrained package has just taken shape in recent days. And Sciortino said, after his announcement, that he would back the emerging tax proposal.
If Sciortino wins the election, he will join six openly gay or lesbian lawmakers in the House of Representatives.
Kara Suffredini of gay and lesbian advocacy group Mass Equality, which has endorsed Sciortino, said his election is particularly important after the retirement of openly gay Massachusetts U.S. Rep. Barney Frank last year.
Sciortino, whatever his liberal bona fides, faces some significant obstacles to election.
As a state representative, he claims a smaller base than the state senators running for the seat. And Sciortino, who raised $152,000 in the first quarter, trails in early fundraising. Clark pulled in nearly $262,000 in the same period. Brownsberger collected $256,000. Spilka and Koutoujian began fundraising later.
The special election to replace Markey is scheduled to take place this fall. The precise date will be set when he steps down to take the Senate seat.
The Fifth Congressional District, which bends through Boston’s northern and western suburbs, is solidly Democratic. The winner of the Democratic primary is expected to win the general election.