The participation rate of 18- to 24-year-olds on July 2 was the highest in history - up from 81% in 2013 to 86.7%.
58% of Australians agree that people of the same sex should be allowed to marry, according to a July Essential poll.
The biggest support comes from young Aussies. Polling by the Marriage Equality Alliance suggest as many as 81% of 18 to 24-year-olds would vote to legalise same-sex marriage.