PROVIDENCE, R.I. — Rhode Island, the only state in New England that has not legalized gay marriage, began taking up the matter this week. The State House is expected to pass a bill Thursday that would allow anyone to marry “any eligible person regardless of gender.”

But the measure faces resistance in the State Senate and its fate is uncertain. Teresa Paiva-Weed, a Democrat who is the Senate president, opposes same-sex marriage but has said she would allow a vote on it in committee. Supporters say that if it gets to the Senate floor, the measure will pass, but opponents are skeptical and state senators are being lobbied heavily by both sides.

Supporters of same-sex marriage have sought to build on the momentum from last year’s elections, when voters in Maine, Maryland and Washington State approved it at the ballot box. Rhode Island is one of several states, including Delaware, Hawaii, Illinois, Minnesota and New Jersey, where supporters of gay marriage are trying to make legislative gains this year.

Of the nine states where gay marriage is already legal, five — Connecticut, Maine, Massachusetts, New Hampshire and Vermont — are in New England. (The other four are Maryland, Iowa, New York and Washington, as well as the District of Columbia.) If the measure passes here, New England would become the first solid block of states in the country to allow gay marriage, underscoring the region’s reputation as the nation’s most liberal, and perhaps its least religious. A Gallup survey found that all six New England states rank among the bottom 10 states for weekly church attendance.