The uniform swing towards Labor at Saturday’s state election saw them easily win the four marginal seats – Adelaide, Elder, King and Newland – they needed to form government and the southern suburbs seat of Davenport, with the landslide victory prompting defeated Premier Steven Marshall to announce his resignation as Liberal Party leader yesterday.

Labor will hold at least 26 Lower House seats in the next parliament, but that number could grow closer to 30 with several Marshall Government ministers in serious trouble.

Marshall’s future in Dunstan remains on a knife’s edge, with Labor’s Cressida O’Hanlon mounting a serious challenge to the outgoing Premier.

With 54.5 per cent of the vote counted, O’Hanlon is ahead 50.5 per cent to 49.5 per cent on two-party preferred, despite Marshall saying on Sunday he “looks(s) forward to continuing to serve the people of Dunstan”.

Scrutineers have told InDaily that on the votes cast on Saturday, Marshall is behind by 143 votes on a two-party-preferred basis, with pre-polls and postal votes to come.

Meanwhile, the ABC is projecting that Transport Minister Corey Wingard will lose his seat of Gibson to Labor’s Sarah Andrews. The Labor candidate currently leads with 53.6 per cent of the two-party-preferred vote with more than 53 per cent of ballots counted.

Minister for Innovation and Skills David Pisoni is also facing an uphill battle in Unley where the Greens garnered around 20 per cent of the first preference vote, putting Labor’s Ryan Harrison within striking distance at 49.7 per cent two-party preferred.

The Liberals could also lose Primary Industries Minister David Basham in a massive boilover in the blue-ribbon seat of Finniss.

Energetic independent Lou Nicholson currently leads Basham 55.1 per cent to 44.9 per cent, although only 40 per cent of the vote has been counted. The swing against the Liberals comes amid discontent from the local branch about the state of health services in the Victor Harbor region, with several local Liberals prior to the election openly canvassing their intention to vote for Nicholson.

Lou Nicholson’s election night party on Saturday. Photo: supplied

The loss of any cabinet minister would only add further insult to injury for the Liberal Party after their Deputy Leader Dan van Holst Pellekaan and Child Protection Minister Rachel Sanderson were both turfed out on Saturday.

Education Minister John Gardner is also caught in an unexpected fight to hold onto his seat of Morialta where there has been a swing of nearly nine per cent against the government.

Gardner told InDaily on Saturday he was “cautiously confident” that pre-poll and postal votes would keep the eastern suburbs seat in Liberal hands, but he sits at just 50.5 per cent on two-party preferred.

Peter Malinauskas’s majority could also be strengthened by a surprise victory in the seat of Waite, where election scrutineers say a complex series of preference flows have left only Labor’s Catherine Hutchisson and independent Heather Holmes-Ross in contention.

Liberal Alexander Hyde appears to be out of the race for Waite while incumbent independent Sam Duluk was not competitive with just 19 per cent of the first preference vote.

The Electoral Commission will today begin counting postal and pre-poll votes. According to ECSA, more than 210,000 people cast an early ballot and more than 170,000 applied for a postal vote.