The ABC election computer is predicting the Coalition has secured majority government with at least 77 seats, as the Liberals appear set to secure Bass, Chisholm, Boothby and Wentworth.

Labor held Bass, while Wentworth and Chisholm were in the hands of independents Kerryn Phelps and Julia Banks prior to the election.

"As far as I'm concerned, on the numbers to come, Bass will be the 76th seat. Postals and absent votes favour the Coalition in Bass and they're already ahead," ABC chief elections analyst Antony Green said.

"At some time today Bass will tick over to become the 76th seat, delivering the Government majority."

Green said he expected Chisholm would become the 77th seat, with Boothby and Wentworth already in the Liberal count.

"The Coalition have a certain 75," Green said.

"Bass will be 76 and Chisholm looks likely to be 77 and 78 is a possibility with Macquarie, but that is in doubt."

Bridget Archer has claimed Bass from Labor's Ross Hart. ( ABC News: Ellen Coulter )

Liberal candidate Dave Sharma had been locked in a nail-biting, too-close-to-call contest with incumbent MP Dr Phelps for the second time in just seven months in Wentworth.

But this time Mr Sharma looks to have prevailed in the seat once held by former prime minister Malcolm Turnbull, reclaiming the seat for the Liberals.

Dr Phelps conceded the election with about 80 per cent of votes counted.

She thanked her supporters, who she said believed in doing politics "differently".

"They believe that there was a sensible centre in Australian politics," she said.

"That it wasn't always about right and left, that it was about right and wrong."

Liberal Nicolle Flint is yet to claim victory in her Adelaide seat of Boothby. ( ABC News: Adam Kennedy )

In the South Australian seat of Boothby, Liberal candidate Nicolle Flint held off a 1.5 per cent swing against the Coalition to edge Labor's Nadia Clancy.

Ms Flint told Sky News she was not willing to declare victory yet despite saying Ms Clancy had called her to concede defeat.

"I'm a bit old-school, waiting for the Australian Electoral Commission to make that final determination and get through those 8,000 or so postal votes still to go," she said.

"They're not counting today, they're counting again tomorrow."

Of the seats in doubt, Labor is ahead in Cowan, Lilley and Macquarie — three seats the party currently holds.

With 84 per cent counted, Macquarie is the closest of those races, with Labor leading by about 300 votes.

Labor held Chisholm from 1998 until 2016, when then-Liberal Julia Banks won the seat — the only Liberal gain in that election.

She quit the party after Malcolm Turnbull lost the leadership and decided against re-contesting the seat as an independent.

Ms Banks instead ran as an independent in Flinders, Health Minister Greg Hunt's seat, but only attracted 14.6 per cent of first-preference votes.