UKIP, which officially supports keeping marriage as it is, has seen a dramatic increase in support in yesterday’s local elections.
Election expert, Professor John Curtice, says UKIP has gained support from voters who are socially conservative on issues like gay marriage.
A poll by ComRes earlier this week showed that all three main parties would lose votes because they support the redefinition of marriage.
In particular the Conservative Party would lose hundreds of local council seats, with much of that support going to UKIP.
One in four voters who backed the Tories at the last general election said they were “less likely” to do so again because of gay marriage.
When the poll was released on Tuesday Colin Hart, Campaign Director for the Coalition for Marriage, called it a “real blow” for David Cameron.
He said: “The Prime Minister has consistently backed the proposed changes to redefine marriage as part of the so called decontamination strategy, but it has not worked.
“Every section of the electorate is highly sceptical about his motives, believing he is pushing this policy in a cynical attempt to make his Party look trendy and progressive. This is the ultimate failure of Blairite triangulation policy.”
On Monday the Northern Ireland Assembly rejected a motion calling for gay marriage in the Province – by an increased majority compared to a similar motion in October.