CHICAGO — A same-sex marriage bill in Illinois stalled in the Senate after gaining traction from a coalition that includes President Obama and the chairman of the state Republican Party, Pat Brady.
While the bill emerged Thursday from a Senate committee, the full chamber declined to vote on the measure, raising the prospect that final action may be delayed until a new legislative session that begins next week. Sponsors postponed the vote because some senators who support making Illinois the 10th state to legalize such unions were absent.
If the House of Representatives takes up the measure when it convenes next week, the Senate may return to vote on it. While supporters weren’t counting on that, they predicted the measure would eventually pass.
‘‘Whether next week, next month, this spring, or in the months ahead, freedom to marry for same-sex couples will be won in the Illinois General Assembly or in the courts,’’ John Knight, who handles gay issues for the American Civil Liberties Union of Illinois, said in a statement from the Chicago office.
On the heels of the first ballot-box victories for gay marriage in November, the effort took shape quickly during the waning days of the legislative session, which many lawmakers expected to be dominated by solving a $97 billion unfunded pension liability.
Elected officials who often avoid commenting on state matters have added their voices to the debate.
‘‘I urge you to vote for marriage equality in Illinois so that our state can be part of the emerging national consensus on this issue of justice,’’ Democratic US Senator Dick Durbin said yesterday in a letter released from his Washington office.
Same-sex couples are now able to marry in nine states and the District of Columbia, home to a combined 14 percent of the US population. In November, voters in Washington, Maryland, and Maine approved the practice. While 30 states have constitutional amendments defining marriage as a pact between a man and a woman only, Delaware, Hawaii, Minnesota, New Jersey, and Rhode Island lawmakers plan to consider or revisit legalization this year.
Brady, the Republican chairman, said he was putting his ‘‘full support’’ behind the bill. ‘‘It strengthens families and reinforces a key Republican value — that the law should treat all citizens equally,’’ Brady told the Chicago Sun-Times in an article published Jan. 2.
A coalition of religious leaders opposes the Illinois bill, and the National Organization for Marriage pledged Thursday to defeat any Republican who votes for it.
The group also called Brady ‘‘unfit’’ to continue as chairman of the party. Brady didn’t return a telephone call seeking comment.
The Washington-based group targeted lawmakers who voted for same-sex marriage in New York, including two Republicans who were defeated at the ballot box last year.
‘‘Any Republican in Illinois who betrays the cause of marriage will be casting a career-ending vote and will be held accountable to their constituents,’’ Brian Brown, the group’s president, said on the organization’s website. ‘‘We will spend whatever it takes.’’