'Not my first rodeo': National Party MP Simon Bridges 'confident' ahead of leadership vote against Chris Luxon

National MP Simon Bridges says he feels confident ahead of National Party's leadership showdown despite some nerves: "this isn't my first rodeo."

He is expected to go up against new MP Christopher Luxon for the job as leader at the 3pm caucus meeting on Tuesday in Wellington.

On Monday night he was showing no signs of dropping out of the contest despite calls for a deal to be done rather than take it to a vote, and reports Luxon had the edge in the numbers.

Speaking to the Bay of Plenty Times at the delayed launch of his book in Tauranga on Monday evening, Bridges said "these things are always close" and tomorrow's vote would be "vital".

"I'm confident it will happen and that from after tomorrow National will unify - we need to, New Zealand deserves us to."

He said he was confident the National Party will leave tomorrow's meeting unified "one way or the other".

He was contesting the leadership because of his experience "and view of where we should be going as a country".

"It's the right thing to do. People will have all their own views but it's not something that I was thinking about on Wednesday morning before this whole sorry saga came out last week."

"But with the vacancy there were a lot of my colleagues who have said to me I need to do this."

Last Thursday, Judith Collins was kicked out as leader by the caucus after she tried to demote Bridges over a crude comment he had made to fellow MP Jacqui Dean in 2016.

The comment related to techniques to improve the chances of conceiving a daughter rather than a son. Dean has since said she did not intend Collins to use the incident - for which Bridges had already apologised - to demote Bridges.

In a Facebook post today, she said she took "no pleasure in being caught up in what was a political power-play that took attention away from the important issues of the day."

It is the first time Bridges has spoken publicly since he threw his hat in for the leadership - hoping for a second go at the job after he was rolled by Todd Muller in 2020.

His rival, Christopher Luxon, has also not spoken to media but is contesting the position - and the early reports were that Luxon had the edge in the numbers.

Former PM Sir John Key is among those backing Luxon - and among those urging the contenders to try to come to a deal over the leadership rather than take it to a vote.

However, it is unclear how convincing Luxon's lead is - Bridges' camp believes there are still several votes in play.