Gay marriage: David Cameron and his party are experiencing a seven year itch All is not quite what it seems though. This is actually a trap and a concerted attempt by the socially conservative wing of the party to bring down the whole bill. It's a trap Labour MPs had appeared to be walking into, with Number Ten fearing they would vote with rebel Tories on the measure. As the Liberal Democrat minister Lynne Featherstone has blogged: "Have Tim and his colleagues suddenly become converts to the cause of equality? Given their public statements I fear what is at work here is rather darker and more cynical - a deliberate attempt to wreck the legislation by introducing extra issues to it that will make it easier for opponents of equal marriage in Parliament to then filibuster, delay and block the legislation. Since she blogged, it appears wiser Labour heads have prevailed, with Labour tabling its own amendment to the legislation to establish an immediate consultation on granting heterosexual couples civil partnerships. Labour's shadow home secretary Yvette Cooper says her party didn't want to see the gay marriage bill "derailed either by the government or by the Tory backbenchers." Number Ten has made clear how fatal the Loughton amendment would be, though it foolishly briefed some rather dubious figures that the cost of altering the bill in this way would amount to £4bn. I've got some sympathy with Mr Loughton's tweet that this figure is "back of fag packet scaremongering." But where ministers appear to have a better argument is that the amendment would seriously delay the passage of the bill, throwing up constitutional complications. David Cameron is right to pick a fight with his party on this issue. Tony Blair won three general elections by confronting core Labour supporters on issues which had made the party unelectable, appealing way beyond his traditional base. The trouble is Mr Cameron hasn't yet proved himself a winner and may never do, having failed to win a majority in 2010. And while Mr Blair lost traditional Labour supporters, he gained erstwhile Tories and swing voters. Mr Cameron meanwhile is losing core Conservatives but failing to pick up disaffected Labour voters. So while he's right to challenge his party on gay marriage, it's a battle he may end up losing to Mr Loughton and his motley crew.