Legislation that would legalize gay marriage in Connecticut passed the state Judiciary Committee on Thursday, and some legislators say the bill is likely to become law.

The bill, which passed 27-15, will now come before the entire state House of Representatives, and then the Senate. Supporters of the proposal said its passage yesterday was a major accomplishment, capping the last six years of lobbying for the measure. Opponents said the bill is all but certain to pass the full House, which they described as unfortunate given the “legitimate, societal function of heterosexual marriage.”

The Judiciary Committee vote comes two years after Connecticut passed legislation to recognize same-sex civil unions, guaranteeing equal legal protections and benefits for same-sex couples.

Representative Mike Lawlor (D) said Thursday’s vote is a victory for same-sex couples. Although civil unions already exist, he said, many people do not understand the significance of them, and other states and the federal government do not necessarily recognize them. Lawlor, who co-chairs the Judiciary Committee, said that tides are moving in the direction of more universal recognition of same-sex marriage. As people have thought about the issue, he said, many opponents have changed their minds — including a few members of the committee who were initially opposed to the bill.

“The only arguments against the bill were fundamentally religious arguments,” Lawlor said. “They included the slippery slope argument — that gay marriage will lead to polygamy, bestiality; that if we end up doing this, people could eventually be marrying dolphins. No real substantive arguments were made.”

But a ranking member on the committee, Arthur O’Neill (R-69), said that he thought the “most cogent” testimony was offered by syndicated columnist Maggie Gallagher, president of the Institute for Marriage and Public Policy, who argued that opposition to gay marriage has nothing to do with bigotry, but rather protects the unique benefits of heterosexual marriage. O’Neill said marriage between a man and a woman has “special significance” because it helps with “raising children and fostering a family unit.”

In her testimony, Gallagher said that marriage centered on three “enduring truths.” These truths, she said, were that sex creates babies, society needs babies and children need both a father and a mother.

But ultimately, committee members rejected those arguments in a party-line vote — the only Republican to support the bill was Sen. Andrew Roraback ’83 — to legalize same-sex marriage. Lawlor pointed to a Quinnipiac poll showing that public opinion in Connecticut was shifting toward supporting same-sex marriage. According to a poll conducted this February, 39 percent of those surveyed said gays should be allowed to marry. Another 33 percent supported civil unions, while 22 percent objected to all forms of legal recognition for same-sex unions. The combined 72 percent that support either same-sex civil unions or marriage is up from 56 percent in 2005.

Lawlor said it was a “very, very real possibility” that the bill would pass the legislature. O’Neill predicted a similar party-line split in the full House, but he said that with Democrats controlling the legislature, there was almost no chance the bill would fail. He added that most of the Democratic opponents to the legislation were members of the Judiciary Committee.

According to the Associated Press, Republican Gov. M. Jodi Rell said again Thursday that marriage should be between a man and a woman. Two years ago, Rell signed the bill that legalized civil unions in the state.

Rep. Pat Dillon (D-92) said the outcome of the vote should have come as no surprise to committee members, who have seen gradual changes made regarding same-sex rights over the past few years. But she said that although the vote was “an important step,” some Connecticut residents may not have been expecting the rapid progress toward gay marriage. She also noted that even some members who would have been skeptical of the bill voted for it because they wanted to preempt court challenges that many on the committee had viewed as inevitable.

“We wanted to step up to the plate, rather than wait for the courts,” Dillon said. “Many of us thought [same-sex marriage] was more appropriate for legislatures to address.”

Dillon added that it was an emotional day, and that for both personal and family reasons, “there were a lot of tears.”