Sydney's south and west key to election victory

The path to victory in the NSW election will hinge on key seats in Sydney's west and south.

Political analysts say battlegrounds in the city's south, southwest, west and northwest will likely decide the outcome of the March 25 poll.

Swings are unlikely to be uniform across the state's 93 seats, as shifting demographics and retiring members thrust just a handful of electorates into play, pollsters predict.

Labor must win five seats to form government and maintain seats it already comfortably holds.

* Parramatta

Election analysts believe the key seat of Parramatta, held by the Liberal party by 6.5 per cent, will almost certainly turn red on March 25.

The swing against the government could be substantial in the western Sydney electorate, above the 6.5 per cent Labor needs to secure a win, according to ABC chief election analyst Antony Green.

"It will be extremely difficult for the Liberal Party to hold it," Mr Green said.

"Of all the seats it's probably the one that Labor has got the best chance of winning."

Parramatta has the state's highest number of renters, a diverse population, and large numbers of young professionals, polling analyst and director of Redbridge Group Kos Samaras tells AAP.

These kind of demographic traits indicate a strong Labor vote, and the seat being Liberal-held is an aberration, he said.

Labor insiders are also quietly confident about taking Parramatta, and say the retirement of current Liberal MP Geoff Lee will help push them over the line.

* Penrith

"Based on the federal results, the Liberals have a reasonable chance of holding this seat," Mr Green said.

"I think they probably have a better chance in Penrith than in Parramatta."

The Liberal Party retained the federal seat of Lindsay, which encompasses Penrith, at the last election with a 1.3 per cent swing to Liberal MP Melissa McIntosh, bucking the national trend of a 3.7 per cent swing to Labor.

Mr Samaras said the western Sydney hot spot has become synonymous with self-made wealth and has a higher proportion of Australian-born voters, giving it an edge with the coalition.

Former Liberal minister Stuart Ayres' incumbency also gives the Liberals a boost.

Contesting the seat for Labor is former Penrith mayor Karen McKeown.

"Penrith is going to be a tight run thing. You could see a situation where the Liberal Party is able to hold on to it, but only just," Mr Samaras says.

One Nation could cause issues for the Liberal Party in Penrith, where Belinda Ann McWilliams is contesting the seat.

"The One Nation vote is largely cannibalising the Liberal primary," Mr Samaras says.

"The Liberal primary in NSW obviously slumped from the 2019 result," he said.

"I would say 60 to 70 per cent of that (slump) has come off their pile and gone to parties like One Nation, not to the Labor Party."

* East Hills

The East Hills electorate is the government's most marginal seat, and had never been held by the Liberal party before 2011.

Mr Green believes East Hills will be particularly difficult for the coalition to hold, adding the past two elections were affected by vitriolic campaigns against Labor's candidate.

Labor insiders are less confident about their chances, citing Liberal MP Wendy Lindsay's incumbency.

Premier Dominic Perrottet has campaigned in the south Sydney seat numerous times alongside Ms Lindsay, including to announce $306 million in community sports funding.

* Leppington

Leppington is a new electorate in Sydney's outer west, taking in pieces of five existing electorates, including Macquarie Fields, Liverpool, Camden, Mulgoa and Holsworthy.

Previous polling booth data makes the seat notionally Labor, will most likely fall to Labor on election night, Mr Green believes.

However, Mr Samaras says voters in the area could go either way, as neither party is familiar with the seat, and swings against the government could be between one and three per cent.

He does ultimately expect Labor to be able to take it over the line.

Camden mayor and small business owner Therese Fedeli will contest the seat for the Liberal Party.

Liverpool City Councillor and treasurer of Local Government NSW Nathan Hagarty is representing Labor.

* Riverstone

Riverstone, takes in the western Sydney suburbs of Marsden Park and Rouse Hill.

It has been held by the government since Liberal MP Kevin Connolly took the seat in 2011.

Previously considered a safe seat for the government, a redistribution and the retirement of Mr Connolly edges the seat back into winnable territory for Labor candidate Warren Kirby.

Representing the NSW Liberals is local man Mohit Kumar, a 19-year veteran of the NSW Police, who is currently working as a police prosecutor.

* Winston Hills

Mr Green says Winston Hills is a must win for Labor if they hope to take government.

The electorate was previously known as Seven Hills, and has had its boundaries redrawn since the 2019 election, slicing Seven Hills incumbent Mark Taylor's margin to under six per cent.

The area has a diverse population and is considered a winnable by Labor insiders, but knocking off the incumbent Liberal member will make taking the seat difficult.

Labor's candidate is deputy lord mayor of Parramatta and small business owner Sameer Pandey.

* Holsworthy

The south Sydney seat has been held by Liberal MP Melanie Gibbons since 2015 but is being contested by former deputy mayor Tina Ayyad, after she defeated Ms Gibbons during preselections last year.

Labor's candidate Mick Maroney is a high school teacher and former police officer and firefighter.