Bill Shorten still believes the majority of Australians will vote to legalise same sex marriage and has urged supporters not to be disheartened by the 'no' campaign.
The opposition leader on Sunday told a 'yes' rally in Melbourne that "the end is almost in sight" for those who have fought and worked towards same sex marriage in Australia.
"I think this argument is winning, but it is by no matter concluded," he told the hundreds of people who had gathered at the State Library of Victoria.
Sunday's crowd was considerably smaller than an earlier 'yes' rally in August, as thousands gathered at Punt Road Oval to celebrate Richmond's grand final win with the team's premiership players.
Not to be outdone by yellow and black, 'Yes' campaigners marched down Swanston Street with 600 metres of bright fabric - 100m for each colour of the rainbow.
Mr Shorten said the debate about same sex marriage and the 'no' campaign has taken a toll on gay people.
"This survey has been exhausting for strong people, and that pains me very much," he said.
"The fact that some Australians have to literally knock on 16 million doors to get permission to validate their loving relationship is tiring."
Greens leader Richard Di Natale said the 'yes' movement had come a long way, but still had a few weeks left before the survey was tallied.
"They're some of the longest, most difficult weeks ahead of us because we have to knock on every door, we have to make those phone calls ... to let people know that in saying 'yes' we take nothing away from anybody, but we give so much to so many," he told the crowd.
On Sunday night, US rapper Macklemore will sing his hit Same Love, a marriage equality anthem, in the pre-game entertainment at the NRL grand final despite protests from the 'no' side, including former prime minister Tony Abbott.
The 'no' side will air ads during the game between the Melbourne Storm and North Queensland Cowboys, which could not be run during the daytime AFL grand final on Saturday.
More than two weeks have passed since the Australian Bureau of Statistics began mailing the Australian marriage law postal survey to enrolled voters on September 12.
The ABS will publish the results on November 15.
