A mere two votes separated the two contenders for the seat of Dubbo at one of the city's polling booths after preferences, in a result revealing the tight contest between them.
Nationals candidate Dugald Saunders and independent Mathew Dickerson remained locked in a battle on Monday as the crucial count continued.
If Mr Saunders holds his early lead and wins the seat, the Coalition will have enough MPs to form a majority government.
On the first preference count, the Nationals candidate - who was preselected after sitting MP Troy Grant announced his retirement from politics - led in four-fifths of the seat's 24 booths, NSW Electoral Commission figures show.
They included Ballimore, Cudgegong Valley, Dubbo College Delroy, Dubbo College South, Dubbo North Public, Dubbo South Public, Eumungerie Public, Geurie Public, Gulgong Hall, Hargraves Public, Lue Public, Mudgee High, Mudgee PCYC, Mumbil Public, Narromine Public, Stuart Town Public, Trangie Central, Wellington Public, Wongarbon Public, as well as Sydney Town Hall.
However he fell short of an absolute majority of votes across the seat, meaning a distribution of preferences was needed and the result was too close to call at the weekend.
By mid-Monday, Mr Saunders was in front overall on a two-candidate preferred basis and had won 14 of the seat's 24 booths, stretching from Lue in the east to Trangie in the west.
But Mr Dickerson was ahead in six of the seven booths in the urban area of Dubbo where votes were cast on election day.
The margin was as small as two votes at Dubbo North Public School, with Mr Dickerson claiming 584 to Mr Saunders' 582.
Mr Dickerson also came out in front at the booths at Buninyong Public, Dubbo College Delroy Campus, Dubbo South Public, Orana Heights Public, and the Wesley Centre.
Mr Saunders claimed the Dubbo College South Campus booth.
The Nationals candidate also won Ballimore, Cudgegong Valley Public, Eumungerie Public, Geurie Public, Gulgong Hall, Hargraves Public, Lue Public, Mudgee High, Mudgee PCYC, Narromine Public, Trangie Central and Wongarbon Public, and the Sydney Town Hall centre.
Outside the city of Dubbo, Mr Dickerson picked up a greater number of votes at Mumbil Public, Stuart Town Public, Wellington Public, and Wellington Scout Hall.
The Daily Liberal understands Mr Saunders secured more of the votes cast prior to election day at early voting centres at Dubbo and Mudgee.
Electoral Commission figures show Mr Saunders also won the Narromine early voting centre, while Mr Dickerson claimed Wellington.
The Shooters, Fishers and Farmers Party recorded a more modest result at Dubbo than it did in the neighbouring seat of Barwon, where it looks almost certain to win.
Candidate Lara Quealy had won 13.14 per cent of first preference votes, the fourth-highest, by Monday morning.
She gained the second highest number of votes at Eumungerie, Gulgong Hall, Hargraves, Mumbil Public and Trangie Central booths.
Country Labor candidate Stephen Lawrence had won 14.44 per cent of first preferences votes, the third-highest overall.