The move has angered supporters of Greg Holland, of Bonnet Bay, who has been the candidate at the past two federal elections, and wants a third chance.

Mr Holland has vowed to stay in the race.

The contest is intense because Labor is confident it can gain the 0.8 per cent swing to win the seat after the retirement of sitting Liberal MP Danna Vale.

Mr Thomas, who was chief of staff to former police minister Carl Scully before taking up a senior position with the Commonwealth Bank, confirmed he would be a candidate for the rank and file ballot on March 6.

He said he was not an "outsider'' to the shire because he had attended Inaburra High School at Bangor, where he was school captain, and is a former member of Illawong Rural Fire Service. His daughter, aged six, belonged to Cronulla Nippers.

"I would be honoured to represent the community where I went to school and where I spent my youth,'' Mr Thomas said.

"If I am successful in the preselection I will move into the electorate soon after.''

Supporters of Mr Holland said head office support for Mr Thomas could cause a backlash from party members in the shire.

Mr Holland said he was pleased party officials had agreed to his calls for a rank and file ballot after it appeared the candidate might be selected by the national executive.

"I have spoken to a number of branch members over the weekend and everyone has encouraged me to run despite the fact there looks like there will be a nomination from outside the electorate,'' he said.

"I believe I am the best local candidate and have the experience and connections with the community to win the seat.''

Who do you think should win the preselection battle?