Tories on gay marriage: Geoffrey Vero and Gavin Barwell

Conservative supporters have sent in "a very considerable number of emails and letters", with some resignations, about David Cameron's support for gay marriage, said one of 20 current and former constituency chairmen who delivered a letter to Downing Street.

Surrey Heath Conservative Constituency Association chairman Geoffrey Vero said it was costing the party votes, and some supporters were no longer prepared to help out with canvassing. He called for a "much more rational discussion" and not for those opposed to be dismissed as "old fogeys".

But Conservative MP Gavin Barwell, who backs gay marriage, said some concerns about churches and gay marriage had been addressed and "we need to convince them the safeguards are there in the legislation".

City analyst Louise Cooper joined in the debate.

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