A nail-biting finish is shaping up in Gilmore, with preferences set to decide the nationally critical seat.
A three-cornered contest between Labor's Fiona Phillips, Liberal Warren Mundine and National Katrina Hodgkinson is complicated by disaffected former Liberal Grant Schultz.
The Milton resident is running as an independent after Prime Minister Scott Morrison endorsed Mr Mundine, a North Shore residents, instead.
Other candidates are The Greens' Carmel McCallum, the United Australia Party's Milton Leslight and Christian Democrat Sera Kolukulapally.
Watching the battle for Gilmore keenly from her retirement at Tuross Head is Dr Gwynneth Singleton, a former associate professor in Politics at the University of Canberra.
She says Labor appeared disadvantaged in the preference tussle.
"The flow of preferences may make it difficult for Fiona Phillips to win the seat," Ms Singleton said.
Ms Singleton said how-to-vote cards showed:
- Mr Mundine - second preference to Nationals
- Ms Hodgkinson - second preference to Liberal
- Mr Leslight - second preference to Liberal
- Ms Kolukulapally - based on preference flows at the 2016 election most preferences would go to Liberal
- Mr Schultz - no preference advised
- Ms McCallum - second preference to Labor
- Ms Phillips Labor - second preference to The Greens
"My reading is that, if voters follow the how-to-vote cards, Fiona Phillips is likely to only get significant preferences from The Greens," she said.
"This means she will have to obtain a very strong first-preference count, close to a majority, to get elected.
"The wild card here is Schultz, standing as an Independent, following his rejection as the Liberal candidate by the party."
It remained to be seen how many Liberal supporters would vote for him and where their preferences would go.
"Where will the second preferences of those voters go, because they have clearly rejected Mundine? Potentially, those second preferences are likely to go to Katrina Hodgkinson for the Nationals," she said.
"Another issue lies with Schultz's decision to indicate on his how-to-vote card that voters mark 1 for him and then fill in the rest of the card with their own preferences.
"Coming so soon after the NSW state election, where voters only had to vote 1 and could leave the other squares blank, it is possible this could impact on the number of informal votes."
Ms Singleton said franking policy could influence the outcome.
"I have heard here in Tuross Head that some rusted-on Labor supporters, upset about Labor's franking credits policy, are now looking elsewhere," she said.
Former Gilmore MP Ann Sudmalis won the seat at the 2016 election for the Liberals, defeating Ms Phillips by a narrow margin of 0.5 per cent. She retired after a bitter falling out with Mr Schultz and other Liberal branch members and has been campaigning for Ms Hodgkinson, along with another former Liberal MP Joanna Gash.