The retirement of existing Member for Flinders Liz Penfold will affect voting according to Adelaide University's head of politics and history Dr Clem Macintyre, but he said it would probably still be a fairly safe Liberal seat, making Liberal candidate Peter Treloar the new Member for Flinders.

"A new Liberal candidate and the absence of a well known and recognisable candidate like Liz Penfold is going to probably have some impact on the Liberals but it's one of the safest seats in the State for the Liberals and they can afford to drop a few per cent without that doing anything."

Mr Treloar's biggest competition is likely to be former SA Nationals leader Wilbur Klein who will run for the Nationals.

The National Party vote went up at the last election when Port Lincoln police officer Hank Swalue was the party's candidate for the seat and Mr Klein has election experience as the Nationals' candidate for Grey in the last Federal election.

"I wouldn't be surprised if the National vote goes up but it is unlikely to go up enough to catch the Liberals," Dr Macintyre said.

The Nationals' best chance will be to peg back the Liberal vote to below 50 per cent.

At the last State election Mrs Penfold was the majority winner with more than 50 per cent of the vote but if the Nationals can reduce the Liberal vote to less than 50 per cent at this election, preferences will be counted, giving the Nationals a better chance.

Dr Macintyre said if all the other parties directed their preferences to the National Party, Mr Klein may have a chance of winning the seat but at this stage it seemed unlikely.

Dr Macintyre said the seat was of interest this election because Liz Penfold had a 2 to 3 per cent personal following and it would be interesting to see if this was transferred to Mr Treloar.

Labor is yet to name a candidate for Flinders and Dr Macintyre does not expect the Labor vote to pick up from the 12 per cent vote attracted in 2006.

"I expect the National vote to pick up but it will be a matter of whether it peels some votes from the Liberals or gathers them up from the other candidates."

Family First is the only other party to have registered a candidate, Grant Wilson.