Fiona Phillips cast her vote in Bomaderry on Saturday morning as the Gilmore electorate turned out in their thousands to have their say in Australia's most marginal federal seat.

The incumbent Labor MP is quietly confident of retaining the seat for the third straight term despite holding on by just 373 votes last time ahead of Liberal rival Andrew Constance after preferences were distributed.

Constance and Community Independent nominee Kate Dezarnaulds are her main threats this time around and the three leading candidates for the seat were busy getting around to polling booths on Saturday.

Volunteers at the Kiama Uniting Church on Saturday handing out how-to-vote cards Photo: The Bugle.

Phillips voted at Bomaderry Public School before heading to Nowra and visiting several spots in the electorate before her team will settle in at Currarong Bowling Club and Recreation Club after the polls close at 6pm as the counting gets underway.

“It has been an absolute pleasure talking with local voters all day today," she said.

“I truly care about this community and I’ve been humbled by so many people who stopped to thank me for helping them or their loved ones.

“This year, my team has knocked on nearly 22,000 doors and made more than 14,000 phone calls in an incredible effort right across Gilmore.

“It’s clear that local people want to see cost of living relief and they want to see investment in local healthcare services.

“That’s what I’ll be proud to deliver under a re-elected Albanese Labor Government.”

While Phillips and Constance did not want to comment on polls in the lead-up to election day which tipped Labor to hold on to the seat, Dezarnaulds has been vocal in saying she believes she can sneak under the guard of the major parties to secure the seat on the back of preferences.

The Australian Labor Party and Coalition are staring down the barrel of their lowest nationwide primary vote as smaller independent parties gain traction.

Constance also voted in the morning, completing his ballot at Sanctuary Point, as part of a hectic final day on the campaign trail which included visits to Illaroo Public School and Berry.

"It's been a tough few years for families and small businesses, and people are ready for a better path forward," he said.

Andrew Constance on the campaign trail on Saturday in Berry.

Former Minister for Foreign Affairs Marise Payne has been by Constance's side on election day, trying to help him reverse the agony of the 2022 election defeat by such a slender margin.

Dezarnaulds traversed the length of the coastal strip as part of her election day campaign, starting in the south at Moruya and dropping in at Nelligen, Batemans Bay, Mogo, Ulladulla, Milton, Sussex Inlet, Sanctuary Point, Vincentia, Nowra, Bomaderry, her home town of Berry where she voted, Gerringong, Kiama and Minnamurra.

Kate Dezarnaulds with supporters on Saturday.

Debbie Killian (The Greens), John Hawke (One Nation), Melissa Wise (Trumpet of Patriots), Adrian Carle (Legalise Cannabis Party) and Graham Brown (Family First) are also on the ballot with their preferences expected to have a considerable say in the final outcome.

A beautiful autumn day greeted voters as they made their way to the polling booths throughout the Gilmore electorate which covers a 200km coastal area from Minnamurra to Moruya.

If you have not voted, you don't have much time left with polls closing at 6pm.