Almost 13 million (78.5% of the eligible population) Australians have returned their surveys in the country’s non-binding postal vote on marriage equality. As counting begins a final poll by Guardian Australia predicts a huge lead for the Yes camp, with final results to be revealed in a week. 64% of those who voted backed Yes, according to the poll, up 4% from similar polls in recent weeks. 31% are believed to have voted No. All public polls conducted since ballots were first issued have shown Yes in the lead, with support ranging between 55% to 66%. More voters over the age of 55, who are more likely to vote No, say they have voted in the survey (94%) than people under the age of 35 (80%). Groups most likely to have voted yes are Greens party voters (92%), Labor voters (79%), those aged 18-34 (77%) and women (69%).