The seat of Polwarth appears to have settled definitively in Liberal hands after flip flopping late into election night.

ABC election expert Antony Green called the race for incumbent Liberal Richard Riordan less than two hours after polls closed on Saturday, but after another two hours new results projected a Labor win.

Labor challenger Hutch Hussein, who would have been the first ever Labor MP to hold the seat, held off declaring victory. It turned out to be a wise move, with further votes putting the seat back into the Liberal basket.

The ABC said "some form of data entry error with pre-poll voting on election night" caused the vote-tallying vacillation.

As of midday Sunday, November 27, Mr Riordan had 52.62 per cent of the two-party-preferred vote to Ms Hussein's 47.38 per cent.

Mr Riordan collected more than 43 per cent of the primary vote, with Ms Hussein getting 29.3 per cent and Greens candidate Hillary McAllister 15.7 per cent.

10.30pm Saturday:

The Liberal stronghold of Polwarth appears to have flipped to Labor in a shock loss for Liberal MP Richard Riordan.

Earlier in the evening ABC election expert Antony Green called the race for Mr Riordan, but subsequent results flipped the projected outcome.

With 73 per cent of the vote counted former state Labor Party president Hutch Hussein held a projected 52 to 48 lead over Mr Riordan, in what was expected to be a decisive margin.

At that stage Mr Riordan had 43 per cent of the primary vote to Ms Hussein's 29.2 per cent, but a sizeable greens vote - 15.9 per cent of first preferences - appeared to have flowed through to Labor.

If Ms Hussein takes the seat she will be the first Labor Member for Polwarth in the history of the electorate.

While ABC has called the race, other outlets have held off and Ms Hussein has stopped short of declaring victory, saying it's "too close to call".

Earlier:

Two south-west elections appear done and dusted, with the Coalition projected to retain the seats of Polwarth and Lowan.

ABC news has called Polwarth for Liberal incumbent Richard Riordan, and has also declared Lowan for National Party MP Emma Kealy.

The two seats were some of the first races of the night to be called, with results coming in less than two hours after polls closed.

With 16 per cent of the vote counted in Polwarth, Mr Riordan has 52.9 per cent to Labor challenger Hutch Hussein's 47.1 per cent.

The result was a surprise after a redrawing of the electoral boundaries theoretically narrowed Mr Riordan's margin from 2018 to under two per cent. The redistribution gouged the normally conservative Terang out of Polwarth, while adding in the Labor leaning areas around Torquay.

The result in Lowan was less of a surprise, with Ms Kealy sitting on a massive 23.5 per cent margin, one of the biggest in the state.

With 26 per cent of the vote counted, Ms Kealy was leading 71.9 per cent to 28.1 per cent.

Both races showed slight swings away from Labor, although that may change as the votes are tallied.

IN OTHER NEWS