UPDATED: Uncertainty about South Australia’s political future increased today with the release of updated Electoral Commission figures showing a massive 320,000 votes left to count.

The figure represents about a third of the total electorate.

With a handful of seats still in doubt, these votes could change the complexion of the result.

This afternoon, Labor’s lead in a number of key marginal seats was shaved, following the counting of postal votes. The postal votes favoured the Liberals in a number of seats where Labor is leading, including Colton, Ashford and Elder.

Despite the narrowing gap, Labor isn’t yet worried about Colton (lead reduced from 571 to 440) or Ashford (835 to 661), and is confident about retaining Elder (down from 746 to 625).

In the other key marginal of Mitchell, Liberal candidate Corey Wingard pulled away from sitting Labor MP Alan Sibbons, extending his lead from 233 votes to 373.

Go to the Electoral Commission website for the latest updates.

The large bulk of the votes yet to be counted – 180,000 of them – are absentee votes cast by people who attended booths away from their home electorate. Of these, 3000 are from electors living overseas or interstate.

With early voting booths opening more than two weeks before election day, 78,000 South Australians chose to cast their vote in person before the end of the campaign – the last week of which is widely believed to have swung votes in Labor’s favour.

An additional 88,000 postal voting forms were distributed, although the Electoral Commission expects only 66,000 of those votes to be returned.

The laborious counting task for all of these votes began this morning, with party scrutineers keeping a keen eye.

With 69 per cent of votes counted, Labor leads in 23 seats and the Liberals in 22. Independents Bob Such and Geoff Brock hold the remaining two seats and the balance of power. A party needs 24 seats to govern in their own right.

The Liberals look certain to pick up the seats of Mt Gambier (held by independent Don Pegler), Bright (held by Labor minister Chloe Fox), and Hartley (held by Labor minister Grace Portolesi).

Liberal candidate Corey Wingard has a slender 233-vote lead in the marginal Labor seat of Mitchell, which was also contested by independent Kris Hanna.

Of the other marginals, Labor is confident of holding Colton and Newland, and it’s also leading in Ashford and Elder.

Labor sources say that the Liberals would need to pick up 54-55 per cent of the pre-poll votes to peg back Labor’s leads in these seats.

In the previous state election, Labor won the pre-poll votes in both Elder and Newland.

Electoral Commissioner Kay Mousley says that a final result won’t be known until Sunday.

Both major parties still have a mathematical possibility of winning majority Government.

If one party of the other achieves a one-seat lead, it is unclear how that would affect the decision-making of Such and Brock, or whether they would make their decision based on other factors.

Liberal leader Steven Marshall is clearly not holding out great hope that the independents will support the Liberals.

He said today his party was the “underdog” to gain their support.