Mormons, Jews, Sikhs and Hindus are being asked to join forces to support an amendment to the state Constitution of California banning same-sex marriages.

An interfaith alliance hopes to place one million signs in front gardens across the state late next month in support of Proposition 8.

Mark Jansson, a Mormon who is a member of the Protect Marriage Coalition, told the LA Times that members of his group are also reaching out to Jews, Muslims, Sikhs and Hindus.

Proposition 8 is an initiative measure on the 2008 California General Election ballot in November.

It would amend the state Constitution to “eliminate right of same-sex couples to marry.”

In May the California Supreme Court overturned a ban on same-sex marriages in the state.

The Court voted 4 to 3 to strike the ban on gay marriage in California, making the state only the second in the US after Massachusetts to allow same-sex couples to marry legally under state law.

Proponents of the amendment, also known as Proposition 8, hope voters in the state of California will overrule the court’s decision.

Opponents of gay marriage raised over one million signatures to place the ballot initiative on the November ballot.

“This is a rising up over a 5,000-year-old institution that is being hammered right now,” Jim Garlow, pastor of Skyline Church, an evangelical congregation, told the LA Times.

“What binds us together is one common obsession: . . . marriage,” Garlow said.

However, a poll released today found that 54% of people likely to vote will oppose Proposition 8, while just 40% support it.

A similar poll last month found 51% of likely voters oppose the ban on gay marriage.

California Faith for Equality has produced a video of religious leaders arguing in favour of gay marriage, demonstrating that there are many people of faith who do not support Proposition 8.