Colin Hart of the Christian Institute at a Coalition for Marriage event

The Coalition for Marriage has announced today that it has received more than 300,000 signatures in support of its petition to keep the definition of marriage restricted to that between a man and a woman.

The organisers behind the campaign have claimed that their petition is now the biggest public campaign since the last parliamentary election in 2010. Colin Hart, the campaign director, said in a statement that the surge in support since the consultation began was further evidence of how unpopular the proposal is with the public at large.

By contrast, the petition launched in support of the proposals by Conor Marron and his partner, Coalition for Equal Marriage, has received only 33,400 signatures so far, despite being backed by the British Humanist Association and the Lesbian and Gay Christian Movement.

Mr Marron has said that while it was sad that so many felt the need to sign the anti-equality petition, “equality shouldn’t be just mob rule.” There are, he added, “things that are fair and right and should be done. The vast majority of people either support what we believe or don’t care very much.”

While, on the one hand, some Tory MPs and several religious groups stand opposed to the proposed changes to introduce civil marriage for same-sex couples, the measure has received cross-party support across all three mainstream political parties. Meanwhile, several religious groups have spoken out against the plans to keep same-sex ceremonies out of religious institution, which, gay-rights campaigner Peter Tatchell has argued is against religious freedom.

The government proposals, on which consultations are now under way, has the personal backing of the Prime Minister, and if implemented, will become law by 2015.