Liberal state election candidate Nathaniel Smith has declared victory for the seat of Wollondilly.
While the official count has not concluded, Mr Smith said he had secured the numbers to declare a win.
Mr Smith said he felt "extremely humbled" by the number of votes he received across the electorate.
"I will not take this seat for granted," he said.
Mr Smith received 38.36 per cent of the total formal votes, according to Electoral Commission NSW.
Counting is underway for ballot papers from Welby Hall, the Wollondilly early voting centre, absent votes, postal votes and iVotes.
Mr Smith's nearest competitor and Independent candidate Judith Hannan received 20.93 per cent of the total formal votes.
Ms Hannan said while it was "unlikely" she would claim the seat, the votes were still being counted.
"I'm just happy we're at Monday and it's still being counted. Normally it's Saturday night," she said.
"It's a huge swing and they need to look carefully [at the electorate]."
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