Updated

Australians will soon begin receiving their postal ballots on legalizing gay marriage as a new opinion poll shows that most of those who intend to vote over the next month are in favor of marriage equality.

More than 16 million registered voters will receive ballots from Tuesday requesting their opinion on whether same-sex couples should be allowed to wed.

An Ipsos poll published in Fair Media newspapers on Tuesday found 65 percent of respondents said they were certain to take part in the survey.

Of those certain to post their ballot papers back, 70 percent said they would support gay marriage.

If the postal survey finds most Australians want gay marriage, the Parliament will vote by December on legislation to lift the prohibition on gay marriage.