CONCORD, N.H. — Opponents of repealing New Hampshire’s gay marriage law said Monday the issue is one of civil, not religious liberties.

About two-dozen members of Standing Up For New Hampshire Families held a news conference to urge the House to kill a bill that would repeal the same-sex marriage law.

The House votes on the bill Wednesday, and repeal opponents believe the vote will be close.

State Rep. Mike Ball, a Manchester Republican, said he went to a segregated school in the South and repealing the law would do the same thing in New Hampshire by relegating gay unions to the separate status of civil unions. “This is a civil liberties issue,” he said.

State Rep. Jennifer Coffey, R-Andover, said the Legislature should not make gay couples into second-class citizens by creating two classes of unions – one for heterosexual couples and one for gay couples.

State Rep. David Bates, the bill’s prime sponsor, proposes repealing gay marriage and replacing it with the civil unions law in place in New Hampshire in 2008 and 2009. Same-sex marriages became legal in the state in 2010.

Marriages in effect before Bates’ proposed law took effect in March 2013 would not be affected, but future gay unions would be civil unions if the bill becomes law. Voters could weigh in through a nonbinding ballot question in November.

Coffey said if Bates’ bill becomes law, the referendum question won’t change the result. “Your vote is not going to count and the law is still going to be repealed,” she said.

Bates argues lawmakers would have time next year to stop the repeal from taking effect if voters supported gay marriage on the nonbinding ballot question.

Greg Kretschmar, a radio talk show host, said everyone deserves the same opportunity to be happy. “The people of New Hampshire do not want the government meddling in their private lives,” he said.

The repeal effort is personal to Mary Dumont and her spouse, Emily French-Dumont.

Dumont, a chef at Harvest Restaurant in Cambridge, Mass., said she spent her whole life looking for Emily and a chance to be married with all the legal protections that come with it.

“I can’t control my personal life. This is who I am,” she said. “When I wake up, I don’t think I’m going to have a ‘gay’ day. I’m a chef.”

The civil unions law previously in effect was considered by gay marriage supporters to be marriage in all but name. Bates’ proposal is intended to return to that law by giving same-sex couples the contractual protections of marriage and requiring them to go through divorce proceedings like heterosexual couples.

Bates said his proposal, a change from an earlier one, will satisfy some critics who said his original proposal failed to ensure the almost 1,900 existing same-sex marriages would not be affected if the law that took effect in 2010 is repealed. The amendment specifically says their marriages will not be affected. Bates said it would replace the current “illegitimate definition” of marriage with one defining it as between one man and one woman.

Democratic Gov. John Lynch has repeatedly said he will veto any attempts by the Republican-controlled Legislature to repeal the law, which he signed in 2009.