Prime Minister Anthony Albanese says Australians will listen to their better angels when deciding whether to support an Indigenous Voice to Parliament on October 14.

It has been 15 months since Mr Albanese opened an election-night victory speech by promising to establish the Voice.

Since then, the issue has become the subject of a long, often highly charged, and sharply partisan debate.

Polls show support for the proposal has fallen – the ‘No’ campaign all but declared victory in two states before the Prime Minister spoke on Wednesday morning.

Now a sprint

But Mr Albanese was upbeat and assured when he announced the referendum would be held on October 14.

He said ‘Yes’ would win as he launched a focused, six-week campaign.

“For Aboriginal and Torres Strait Islander people, this has been a marathon,” he said. “For all of us, it is now a sprint.

“It’s a moment calling out to the best of our Australian character.”

Elizabeth, a poor suburb 30 minutes north of Adelaide that was once home to a long-closed Holden manufacturing plant, might have seemed an unassuming backdrop for Mr Albanese’s historic announcement.

But the choice reflected a national fault line on the Voice, which a Newgate poll released on Wednesday found is down, with a ‘Yes’ vote at 46 per cent to a ‘No’ vote of 54 per cent.

‘No’ campaigner Warren Mundine claims Queensland and Western Australia are nearly locked in against the Voice.

That makes South Australia crucial. But the state is also divided between urban ‘Yes’ voters and strong opposition blocs in regional areas.

Elizabeth might represent the political middle ground and home to the demographics whom Mr Albanese and the ‘Yes’ campaign must persuade if they are to prevail six weeks from now.

“Biggest supporters for No?” wrote RedBridge pollster Kos Samaras. “Boomers without a university degree.

“Then followed by 40+ year olds with lower incomes, especially in the outer suburbs of larger cities and regional Australia.”

‘Gen Z’ voters and people who speak a language other than English at home consistently record levels of support at 60 per cent or above, Mr Samaras said.

Nothing changes

The referendum, the PM said, would be a decisive moment in the history of reconciliation.

“Because Voting ‘No’ leads nowhere; it means nothing changes,” Mr Albanese said.

“Voting ‘No’ closes the door on this opportunity to move forward.”

The last prime minister to preside over a referendum, John Howard, who campaigned against the failed republic referendum in 1999, called on opponents of the Voice to “maintain their rage” for the next six weeks.

Opposition Leader Peter Dutton said the Voice was “not going to provide the panacea that the Prime Minister is promising”.

But the referendum has exposed divisions in the party’s constituency, which could deepen throughout a campaign ‘Yes’ advocates hope to win by approaching voters door to door.

Former NSW premier Mike Baird became the latest Liberal to split with his federal party on the Voice, declaring it a “chance to make a difference”.

“Why wouldn’t you invest in all pieces of legislation being considered and getting a Voice into them?” he said.

“From my point of view, this is incredibly constructive.”

Mr Dutton predicted a tight poll and said the ‘No’ campaign would be at a disadvantage on the ground over the next six weeks.

Australian Council of Trade Unions secretary Sally McManus said the union movement would mobilise resources behind the ‘Yes’ campaign.

“The union movement has listened to its membership, who are keen to walk with their Indigenous colleagues, and we will be supporting members to campaign on this issue,” she said.

But a report released on Wednesday found that the online referendum campaign has not been fought evenly.

Private intelligence firm Recorded Future warned domestic and foreign actors, including China’s Communist Party, were spreading divisive narratives about the referendum online.

It identified false claims circulating on social media and underground channels online, including that the Voice was part of a larger Jewish plot to undermine Australian sovereignty or was a Communist trojan horse.