The Liberals' James Stevens, who looks set to retain the South Australian seat of Sturt, says his party has been sent a clear message voters want action on climate change.
Mr Stevens is the incumbent for the eastern Adelaide suburbs seat, which is usually considered a safe Liberal seat.
He said while he was still not yet confident to claim victory over Labor's Sonja Baram, postal votes were so far in his favour.
"At this stage I'm getting a strong return on the postals, about 58 per cent of the postals are coming my way," he said.
"I might end up winning by 1,500 or 2,000 votes, but it is a very significant message that's being sent to me and the Liberal Party on the weekend in Sturt, as is the case across the country."
Mr Stevens said voters in Sturt had turned their backs on the major parties, favouring the Greens in what he saw as a clear call for action on climate change.
"Liberals [voters] chose the Greens as an option on Saturday, I think in most cases to send a message, I don't think they wanted to move to the Labor Party otherwise they would have voted for the Labor Party, but I think they felt that the Liberal Party was failing to understand their genuine concerns on climate change action in particular," he told ABC Radio Adelaide.
"That wasn't just the case in Sturt ... I might have been lucky enough to survive, unfortunately most others [in similar seats] haven't, but the message is unequivocal."
Mr Stevens said the Liberal Party had failed to make clear to voters what it had already achieved on climate change.
"I think we had followed a difficult path towards making our commitment to net zero by 2050 and that lost a lot of the capital and value we should have got from that important milestone decision that we made," he said.
"We were doing a lot more than people understood we were doing, but also I don't think it was enough."
He said a shift in attitude would be the only way to win voters back, and the party now needed to focus on holding the Albanese government to account.
"The Liberal Party is a party that should aspire to always be running our country, winning elections and being in government and if we're not prepared to listen to what people in seats like Sturt want then we won't be in government," he said.
South Australian Liberal Senator Simon Birmingham agreed the Liberal Party had to shift its attitude and take further action on climate change.
"If we continue down a pathway where people believe we are not genuine about action on climate change – and that is the real challenge there – that even with the work that was done to achieve a commitment a net zero , the process of getting there was so messy and so untidy and had opponents within the Coalition speaking out against it that people didn't think we were genuine in pursuing that commitment," he said.
"We absolutely need to make sure that we work to build a majority of support on issues that matter to Australians and environment, environmental management, climate change do matter, they need to be handled responsibly and not sacrifice jobs and business and industry across the country."
Results 'catastrophic for conservative side of politics'
Greens candidate Professor Barbara Pocock looks set to gain a seat in the Senate, doubling the number of South Australian Greens senators.
Professor Pocock said South Australia was part "of what is a very significant shift across our country".
"The conversation so much is about the disappointment of the last decade."
She said it was a misconception that action on climate change and a strong economy were mutually exclusive.
"It's a big mistake to pose those two things as opposites of each other," she said.
"If we don't embrace the renewable revolution, we are already part of it here in this state of course we are leading in our country, then we will cost jobs of the future.
"Young people understand that, many people see it and they want us to embrace even more quickly things like electric vehicles [and] green technology, which will expand our manufacturing."
