The NSW Greens have announced farmer and former high school teacher Tony Lonergan to contest Upper Hunter, the third most marginal seat in next month's state election.
Mr Lonergan's performance and preference flows could be crucial in an electorate held by Nationals MP Dave Layzell on a tiny 0.5-point margin after a boundary redistribution.
Labor has announced Peree Watson, the daughter of the late Hunter mining union stalwart Mick Watson, as its Upper Hunter candidate in what will be an important contest in the context of what is expected to be a tight race to form government.
Preference flows are less influential at elections in NSW, where assigning preferences is optional, but they can still deliver victories to candidates who trail on first preferences.
The Greens' Sue Abbott attracted only 3.5 per cent of the primary vote in the 2021 Upper Hunter by-election, but the electoral redistribution could improve the party's showing on March 25.
Mr Layzell won the by-election with an increased 5.8-point margin for the Nationals, but his notional advantage is just half a percentage point after the redraw deposited about 6500 voters from the Labor-held Maitland electorate into Upper Hunter.
Upper Hunter gained the entire town of Branxton, a Labor stronghold, in the redistribution and lost 5000 rural voters to the seats of Tamworth, Dubbo and Bathurst.
Labor's candidate in the 2021 by-election, mining union official Jeff Drayton, won only 21 per cent of the primary vote to Mr Layzell's 31 per cent.
Twenty per cent of preferences flowed to Labor that year and 16 per cent to the Nationals. The other 64 per cent exhausted during the preference count.
Pauline Hanson's One Nation, which won 12.3 per cent of the primary in 2021, does not plan to have a candidate for Upper Hunter this year.
The Shooters, Fishers and Farmers Party lost Singleton businesswoman Sue Gilroy as a candidate during an ugly internal stoush in December but plans to name a new challenger next week.
Ms Gilroy won 12 per cent of the primary vote in 2021.
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Mr Lonergan lives near Muswellbrook on the merino and cattle farm where he grew up.
He taught science for 20 years at high schools in Muswellbrook, Aberdeen and Scone.
"Since coming home in the '80s I have seen a transformation of the Valley," he said.
"The coal industry has expanded unchecked, completely altering the landscape, polluting the air and fundamentally changing the social balance of the Upper Hunter.
"The impact has been particularly severe on small rural communities like mine."
Mr Lonergan accused the government of "double-speak" on climate change "while continuing to release land for exploration and approving coal and gas projects".
He said expanding the Mt Pleasant and Hunter Valley Operations mines to 2048 and 2050 was not consistent with addressing climate change.
"The devastating and increasing costs of extreme weather events in NSW and across the world makes a mockery of any true cost-benefit analysis of these projects."
He said he also supported rural communities resisting the laying of the Hunter gas pipeline across their land.
"We need to implement policies that attract and sustain the industries of the 21st century.
"We have fantastic competitive advantages in our electorate, an abundance of available land, first-class transport infrastructure connecting us to the port of Newcastle and a skilled and adaptable workforce."
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