Three weeks after New Hampshire gay marriage law came into force, opponents are fighting to get it repealed.

The House Judiciary committee is holding hearings on two Republican-sponsored measures today.

One would repeal both gay marriage and the state’s 2007 civil unions law, while the other calls for a state-wide referendum on a constitutional amendment to restrict marriage to one man and one woman.

Although five US states currently allow gay marriage, the right has never been granted by voters and this is something opponents hope to capitalise on.

Republican Representative David Bates is leading the campaign to get a voter referendum on the issue

He told the Associated Press that petitions are being circulated in towns which hold meetings this spring to persuade local councils to pass non-binding resolutions in favour of lawmakers drawing up an amendment to restrict marriage to heterosexuals.

Although opponents know it is unlikely the Democratic-controlled state will repeal gay marriage this year, they are hoping Republicans will win control of the Statehouse this November.

Thirty-one states have voter-led constitutional bans on gay marriage.