The YouGov-Advertiser poll found if an election was held in South Australia on Friday, Labor would win easily with 37 per cent of the primary vote ahead of One Nation at 22 per cent and the Liberals at 20 per cent.
The results were published ahead of the first debate of the campaign between Premier Peter Malinauskas and Liberal leader Ashton Hurn on Friday.
Labor looked to be in an unbeatable position, with its highest two-party preferred result ever regardless of which party is second, the poll found.
YouGov Director of Public Data Paul Smith said that if an election was held on Friday, Labor would win the largest two-party preferred vote since it formed in 1891.
The Liberals would lose at least half their current 13 seats, which would be the worst result for the conservative side of politics since self-government in 1857.
"Almost half the voters in the state see the Liberal Party as a fringe party not capable of governing the state while 84 per cent view the Labor Party as a mainstream party," he said, ahead of the March 21 election.
"It is this view of 44 per cent of the electorate that Liberals are not a mainstream choice that is driving Labor's record win margin."
Should the election be held on Friday, the statewide two-party preferred vote would be Labor on 59 per cent to Liberals' 41 per cent - a swing to Labor of 4.4 per cent - or Labor on 60 per cent to One Nation with 40 per cent, a swing to Labor of 5.4 per cent.
Mr Malinauskas is the preferred premier by +44 per cent (64 per cent to Hurn's 20 per cent).
Fifty-five per cent of voters see the state as heading in the right direction, while 52 per cent think the government deserves to be re-elected.
Flinders University public policy associate lecturer Josh Sunman said winning just three seats was a realistic result for the Liberals.
"This is genuinely apocalyptic for the Liberal Party in South Australia," he said.
"The government's got a pretty strong campaign going, they're sticking to their narrative of building SA, but the Liberals don't have a narrative, and that's what's really hurt them in the campaign."
Mr Malinauskas's net satisfaction is +36, while Ms Hurn is +7.
The Liberal leader will have the chance to push the opposition's agenda when debating Mr Malinauskas at The Advertiser's Future SA event on Friday.Â
One Nation has named former federal Liberal senator Cory Bernardi to lead the party's upper house ticket at the election and will field candidates in every lower house seat.
Mr Smith said 22 per cent equalled One Nation's highest ever state vote in Queensland in 1998.
But the One Nation vote is seven per cent lower than YouGov's polling of their federal vote in SA, due to the greater popularity of the state Labor government and the large number of high profile independents in regional electorates.
"The popularity of independents as a non-major party choice will be a major barrier to One Nation winning in the regional electorates where there is an independent choice," Mr Smith said.
"The Liberals will finish third on primary votes in at least half the state's electorates and it will be their voters' preferences that will decide whether One Nation can win any lower house seats."
26°C