National leader Judith Collins is promising National will be less combative during this term of Parliament after a new poll showed their support at less than half of Labour's.

She is also dismissing questions about new National MP Chris Luxon registering on the preferred Prime Minister poll.

Collins said it was "delightful" but it was, in the end, pretty normal.

Luxon was at 2 per cent on the 1News/Colmar Brunton poll – Collins was at 8 per cent.

"Judith's a great leader, I love working with her and she's absolutely brilliant," Luxon said when asked about the preferred Prime Minister rankings this morning.

The party preference poll showed one of the widest gaps between National and Labour in modern history.

Labour was at 53 per cent, National at 25 per cent – the latter more or less unchanged from election night, but Labour was up 3 percentage points.

Speaking to media ahead of National's last caucus meeting of the year, Collins said the party needs to show New Zealand the "new National".

"We have to act less like a government and more like a government-in-waiting."

That means putting forward National's policies and not being in opposition to everything the Government puts up, she said.

"There are some things that we should give unity and support to the Government for – there are other things, where they are absolutely against our principals, [we will] stand up against."

Luxon was singing the same tune as his leader.

"We have got a lot of work before us in the National Party to rebuild trust, and rebuild relevancy."

Asked if Collins should be watching her back, Luxon said: "Absolutely not."

"Judith's a great leader, I love working with her and she's absolutely brilliant."

On his own leadership ambitions, he said: "I'm on week five and I'm just trying to master what I'm trying to do and that's mastering the portfolios."