Deck stacked against NSW Libs as they fight tide: Kean

NSW Treasurer and Deputy Liberal Leader Matt Kean says the deck is stacked against the Liberals in securing an unprecedented fourth term of coalition government in NSW.

"Fighting the tide of history is like fighting gravity. The deck is stacked against us here," Mr Kean told ABC Television on Saturday.

"So, it is going to be Mount Everest to climb."

Early counting has indicated a strong swing toward Labor. 

A slew of 12 coalition MPs announced their retirement ahead of the state election, but Mr Kean said all government's went through generational change.

"A number of those people retiring were there since the O'Farrell government was elected in 2011," he said.

"There is always generational change. Whether we were able to project that to the community will be seen tonight."

Former NSW premier Mike Baird was optimistic a historic fourth term could be on the cards for the coalition, led by Premier Dominic Perrottet.

Mr Baird said victory for Mr Perrottet was still possible but the road would be difficult.

"There is a pathway, but it's tough. I think everyone's nervous and I'm sure the Labor Party are as well," he told the Nine Network on Saturday.

The latest Newspoll on election eve predicated victory for NSW Labor, who lead the coalition 54.5 to 45.5.

Education Minister and Nationals MP Sarah Mitchell said her nerves were in check after spending time working the polling booths in recent weeks.

"I don't think the baseball bats are out for the government but I think it's going to come down seat by seat."

Her party hopes to retain the 12 seats they hold, with ambitions for other regional seats including Greens-held Ballina, and former Shooters Fishers and Farmers seats of Barwon and Murray, now held by independents.

Earlier, pink cupcakes, blue shirts and plenty of sausages greeted the premier while casting his vote alongside his wife Helen and the couple's youngest daughter, Celeste.

"It's a very important day for the future of our state - there's a lot at stake," Mr Perrottet told reporters at Beecroft in his seat of Epping in northwest Sydney.

"Our party has been a team for over 12 years that has transformed NSW ... We've turned the economy around, built the schools and hospitals, the trains and motorways that's transformed people's lives."

He also lauded the coalition's economic credentials for getting families through rampant inflation.

"You can't support households if you don't have a strong budget. It is strong economic and financial management that ensures downward pressure on household budgets ... and we've done that."

Treasurer Matt Kean, who reportedly has a testy and pragmatic relationship with the premier, was coy about his political ambitions after a possible coalition loss.