It has emerged that the government is not going to introduce tax breaks for married couples in next month's Budget, and the news has reignited Tory anger over Cameron's support for gay marriage.
The two issues are connected in the minds of Tory backbenchers, as they see it as a matter of Cameron's priorities on gay vs heterosexual marriage. There had been speculation that Cameron would bring in married tax breaks in order to appease party members who are anti-gay marriage.
The government is to vote on gay marriage next week.
This comes as a ComRes poll for the Daily Telegraph suggests that one in five Conservatives would "definitely not" vote for the party in 2013 if the Government continues with plans for same sex marriage, and The Times reports that members are leaving the party "in droves" over the issue. According to The Times, those quiting number up to 100 in some seats. It quotes Tory MP David Burrowes saying: "There's serious unrest in the grassroots. You cannot avoid the fact that the troops are unhappy. People are drifting away."
According to the FT, at least half the party's backbenchers will "revolt" against the move - although, as my colleague George Eaton wrote:
Should Conservative cabinet ministers vote against equal marriage, it will not qualify as a rebellion because David Cameron has offered a free vote to his MPs.
However, the split within the party over the vote will heighten speculation over a 2015 leadership change for the Tory party. As George Osborne said, gay marriage acts as a litmus test for how well efforts to modernise the party are working, and the widening gulf between members suggests a good portion of the party is a long way behind.