Almost 12 million Australians have voted in the same-sex marriage survey - and it's great news for the Yes campaign

Marriage equality campaigners in Sydney. Photo: Saeed Khan/AFP/Getty Images / File

SYDNEY — The Australian Bureau of Statistics says a whopping 74.5% of eligible voters have returned their ballot papers in the national survey on same-sex marriage.

The ABS said it had received an estimated 11.9 million survey forms by last Friday.

A turnout this high is encouraging news for marriage equality campaigners, as the voluntary nature of the survey introduced an unpredictable dynamic in terms of public response. With published polling finding support for marriage equality is 60% or higher in the Australian community, higher turnouts increase the likelihood that the Yes campaign can secure a majority of votes.

Marriage equality campaigners were already bouyed by high levels of participation three weeks ago, when turnout was estimated at 9 million ballots or around 57% of eligible participants.

The big jump in turnout levels — it was estimated at 10.8 million in the last ABS update — is due to a change in how the ABS is counting. Forms are now being physically scanned, whereas previously the ABS was estimating the number of ballots received by weighing them.

The ABS estimates it received an additional 300,000 forms last week.

The survey closes on November 7, and results are expected on November 15.

Prime Minister Malcolm Turnbull has said he expects marriage equality to be legislated quickly if the result is in favour of the Yes campaign.

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