Australians care more about same-sex marriage than Americans do about who leads their country, according to a comparison of turnout figures from recent polls.
But some recent votes around the world have drawn a response far greater than either.
The Australian Bureau of Statistics (ABS) has released its latest estimate of the number of returned survey forms in Australia's same-sex marriage postal survey.
Australians' response has now exceeded the turnout for the 2015 UK general election, and is closing on participation in the Brexit vote.
10.8 million Australians — 67.5 per cent of those eligible — have filled out and mailed back their forms.
More than nine million forms were returned prior to the end of September.
Approximately 800,000 forms have been returned each week over the previous two weeks.
ABS deputy statistician Jonathan Palmer, said it was "pleasing" to see another steady increase on the amount announced last week.
"We've still got a couple of weeks to go," he told ABC News.
"We're seeing a steady flow now, and each time we make an announcement about the participation we tend to get a bit of an uptick in calls to our information line."
Voting at state and federal elections in Australia is compulsory, but at local government elections and the 1997 constitutional convention vote it has been optional.
These elections have been analysed by ABC election analyst Antony Green.
The highest recent participation rate was at the 2014 Tasmanian local government elections, where it was at 54.6 per cent.
Internationally, the 1995 independence referendum in the Canadian province of Quebec attracted votes from 93.5 per cent of eligible voters.
The 2014 Scottish independent referendum attracted 84.6 per cent of registered voters.
The 2016 Brexit referendum for the UK to leave the European Union attracted a turnout of 72.2 per cent.
Of these only Brexit was successful, with 52 per cent support.
The three previous US presidential elections have attracted turnouts of between 54 and 59 per cent.
Labor to back Smith bill
If the Yes vote is successful in the survey, the Labor Party will support a private members bill put forward by WA Liberal senator Dean Smith.
Federal Labor MPs have decided on this course of action on the basis it provides an acceptable compromise and has the best chance of succeeding.
The bill would explicitly allow religious figures and celebrants to object to marrying a gay couple.
The deadline to request replacement forms is 6pm this Friday, October 20.
The ABS advises forms should be posted back by October 27 to ensure they are counted.