Dr Kotvojs beat out Queanbeyan-Palerang councillor Mark Schweikert in Saturday's party vote by a comfortable margin. She will be named the Liberal candidate at an event on Sunday morning.

Dr Kotvojs lives in Dignams Creek and is described by the party as a former teacher, coastal geomorphologist, beef farmer and small businesswoman. She contested the seat at the 2019 election, losing to Dr Mike Kelly despite securing a swing of more than 2 per cent.

The byelection was triggered by Dr Kelly's resignation, announced on April 30 after the former army colonel experienced months of ill health.

The election has already been thrown into chaos after Bega MP Andrew Constance put his hand up to run for the federal seat but withdrew from the contest after a sudden change of mind.

Mr Constance said "Labor will be rubbing their little hands together" after his state colleague, Nationals leader and NSW Deputy Premier John Barilaro, torpedoed his plans to stand for Eden-Monaro by describing him as a c--- in text messages revealed in a story in the News Corp press.

Mr Barilaro had himself just dropped out of contention for the seat, leaving many to consider Mr Constance a front-runner to succeed Dr Kelly.

Communities in Eden-Monaro bore the brunt of the summer's bushfire crisis, with both Mr Constance and Labor's candidate for Eden-Monaro Kristy McBain rising to national prominence through the way they represented their communities.