CANBERRA, Australia (AP) — A record number of Australians enrolled to vote in a referendum that would create an Indigenous advocacy body, as the first ballots for constitutional change are set to be cast in remote Outback locations next week, officials said on Thursday.

The referendum to be held on Oct. 14 would enshrine in Australia’s constitution an Indigenous Voice to Parliament. The Voice would be a group of Indigenous representatives who would advise the government and legislators on policies that effect the lives of the nation’s most disadvantaged ethnic minority.

When enrollments closed on Monday, 97.7% of eligible Australians had signed up to vote, Australian Electoral Commissioner Tom Rogers said.

That was the largest proportion of any electoral event in the 122 years that the Australian government has existed. The previous record was 96.8% for the federal election in May last year.

Rogers said high public interest in the Voice was a factor in the large enrollment.

“There is a factor that where people are interested in the event and there’s a lot of media coverage of the event, they’re more likely to enroll and participate,” Rogers told reporters.

Voting is compulsory in Australia so voter turnout is always high. Of Australia’s population of 26 million, 17,676,347 are enrolled to vote in the referendum.

Early voting will begin on Monday at remote and far-flung Outback locations. Officials will use helicopters, boats and airplanes to reach 750 of these voting outposts in the three weeks before Oct. 14.

The referendum is Australia’s first since 1999 and potentially the first to succeed since 1977.

Rogers said he was concerned by the level of online threats that staff at the Australian Electoral Commission, which conducts referendums and federal elections, were being subjected to.

“This is the first social media referendum in Australia’s history,” Rogers said.

“We’ve certainly seen more threats against AEC than we’ve seen previously which I think, frankly, is a disgrace,” Rogers added.

Electoral officials were attempting to counter online disinformation, which appeared to be homegrown rather than coming from overseas, he said.

“Some of the stuff we’re seeing still, frankly, is tin foil hat-wearing, bonkers, mad, conspiracy theories about us using Dominion voting machines -- ... we don’t use voting machines — erasing of ballots, that’s a cracker,” Rogers said.

“They deeply believe whatever they’re saying. So what I think our job is to just put accurate information out there about what the facts are,” Rogers added.

In the United States in April, Fox News agreed to pay Dominion Voting Systems $787.5 million to avert a trial in the voting machine company’s lawsuit that would have exposed how the network promoted lies about how the machines cost former President Donald Trump the 2020 presidential election.

Australian elections and referendums use paper ballots marked with pencils.

The Voice referendum would be the first in Australian history to be passed without bipartisan political support. The center-left Labor Party government supports the Voice. The main conservative parties are opposed. Business, religious and sporting groups all support the Voice.

But opinion polls suggest that most Australians do not and that majority is growing.

Proponents see the Voice as a mechanism to reduce Indigenous disadvantage. Indigenous Australians account for 3.8% of the population and they die around eight years younger than Australia’s wider population.

Opponents divide themselves into progressive and conservative “no” voters.

The conservatives argue the Voice would be a radical change that would create legal uncertainty, divide the nation along racial lines and lead to claims for compensation.

The progressives argue that the Voice would be too weak and Indigenous advice would be ignored.