One Nation's Cory Bernardi talks 'rookie error', Liberal MP dissents on candidate controversy ahead of South Australian election

The South Australian election campaign's final weekend has seen an admission of a "rookie error" from One Nation's Cory Bernardi, while a federal Liberal MP has expressed reservations about the decision to part ways with a controversial candidate.

Early voting opened at 59 centres across the state on Saturday, with electors for the first time not needing to provide a reason for casting their ballots before polling day.

According to the state's electoral commission, a record number of early voters turned out, with more than 67,000 votes issued on the first day.

The premier and the opposition leader were both out on the campaign trail, with Labor committing to a new state gymnastics centre the party said could be used to help train Olympians.

At an early polling station, One Nation's lead upper house candidate Cory Bernardi discussed his decision last week to stand by comments, made almost 14 years ago, linking gay marriage to the social acceptance of bestiality.

Today, he said he did not regret that stance. But he conceded it would have been better if he had avoided being drawn on his previous remarks.

"I should have probably just said, 'No, move on, let's talk about things that matter to people'," he said.

"Instead, I tried to answer the question. I won't do that again.

Mr Bernardi was also asked about former Liberal candidate Carston Woodhouse, whose controversial comments about Islam, feminism and same-sex marriage this week came to light.

Mr Bernardi said the matter was "another scandal for the Liberal Party". But he added that "people are allowed to have their own views".

The SA Liberal Party this week said Mr Woodhouse had "agreed to withdraw" his candidacy for the party after being asked to step down.

But federal Liberal MP Tony Pasin expressed reservations about that outcome.

"I was confused to learn about it because I'm someone who thinks the Liberal Party's fundamental [tenets] are freedom of thought, religion, association," he said.

Mr Pasin said while he had not seen Mr Woodhouse's comments, he believed the Liberal Party was a "broad church".

"If what we're saying is that committed Christians, perhaps people with strong views, can't be endorsed as candidates, that's a difficulty — but, as I say, I haven't seen his comments," he said.

$100m new gymnastics hub

After Friday's debate with Opposition Leader Ashton Hurn, Premier Peter Malinauskas stepped up campaign efforts with an announcement he said would complement his party's policy to keep children off screens.

Mr Malinauskas said a re-elected Labor government would build a new $100 million facility for Gymnastics South Australia in its next term of office, to be potentially jointly funded with the federal government.

He said the facility in "central metropolitan Adelaide" would replace the "leaking" and "decrepit" existing gymnastics centre in the city's southern suburbs.

"It's been engaged with federally, and we continue to pursue that.

"The assessment of the current site is that to try and repurpose and refit it, you'll actually end up with potentially an even more expensive outcome or a substandard one."

Mr Malinauskas said if the new facility were ready in time, it would be available for athletes ahead of the 2032 Brisbane Olympics and Paralympics.

Gymnastics SA praised the announcement, saying it would deliver for the "nearly 5,000 children sitting on waiting lists wanting to do our sport".

"This is obviously an enormous opportunity to bring them into our sport and have some of the life lessons and fundamental skills that everyone needs," acting CEO Kent Davis said.

Fuel prices 'number one issue'

Mr Malinauskas was again asked about One Nation's strong showing in recent polls. He said such support reflected "legitimate grievances within the electorate".

But he described the party as a "policy-free zone".

"The rise of populism around the world is something I'm worried about — populism has real-world consequences," he said.

"Look at the price of petrol, for instance."

Earlier, Mr Bernardi was bullish about One Nation's prospects, saying it was gaining ground in Labor seats.

"You can go into the northern suburbs of Adelaide, which is traditional Labor territory, and we get a very welcome reception there," he said.

"Right now we've got a government that's focused on circuses — there's not much bread there."

The opposition leader, who on Saturday met voters at the Tanunda Show in the heart of her electorate, said the "number one issue" at the moment was fuel security.

"I'm interested to know how much supply we've got here in South Australia," Ms Hurn said.

"I have spoken directly with the premier, and his team are facilitating a briefing for me. So, I really do thank him for that because this is a bipartisan issue.

Late on Saturday afternoon, the Electoral Commission of South Australia (ECSA) provided an update on early voting figures.

In a statement, ECSA said it was "safe to say" record numbers of early voters had turned out across the state.

It said more than 67,000 votes had been issued — almost five times as many as the just over 14,000 on the opening day of early voting four years ago.