The electorate, previously held by former deputy premier John Barilaro, came down to a margin of 5.4 per cent of two-party preferred votes, it was revealed on Tuesday.
Monaro takes in the centres of Queanbeyan, Braidwood, Jindabyne, Cooma and the Snowy Mountains region, and has never been held by a woman in its 165-year history.
On first-preference votes Ms Overall took 45.96 per cent, beating Labor candidate Bryce Wilson, who gathered 31.95 per cent.
It was a safe result for The Nationals, but is a swing against the party of more than six per cent.
It comes after the Coalition suffered swings in the formerly safe seat of Willoughby, where Liberal candidate Tim James retained the seat despite a swing of more than 17 per cent, and Labor took a seat from the Liberals in Bega in a 12 per cent swing.Â
"It was a long campaign but with the support of family, friends, the NSW Nationals, members of parliament, and the many volunteers on the ground, I am happy to say that what we have achieved is a great success," Ms Overall said Tuesday.
She began her run for the seat in October after Mr Barilaro's resignation, and said she was committed to school projects for the community.
"I still promise now, as I promised throughout the entire campaign, that I will work hard for the people of Monaro," she said.
"Delivering on a new high school in Bungendore and keeping Googong primary school on time and under budget, are two of my biggest priorities.
"I will also be working hard to further improve healthcare across our communities, increase job security, and increase housing availability and affordability."
NSW Deputy Premier Paul Toole said Ms Overall would bring strength and commitment to her role as member for Monaro.
"I know Nichole will work hard to prove to everyone that voted for her that their vote was worth it," he said.
"She's a fighter, she's dedicated, and she's intensely passionate about her community."
28°C