Phil Twyford backs 'right-wing, red meat' Judith Collins

A high-profile Labour MP wants Judith Collins to lead a "hard, right-wing, red meat National Party" that has the "courage of its convictions".

Phil Twyford told The AM Show on Friday - perhaps facetiously - the "problem with the modern National Party is they don't stand for anything".

"What did John Key ever achieve? Can anyone remember anything that he did? If Judith is the leader, [she] will bring back hard free market policy, locking up the crims and throwing away the key."

He compared her to hardline British Tory Prime Minister Margaret Thatcher, leading to howls of protest.

"How can people even put me in the same league? I'm so much softer," Ms Collins said of her hero.

Her opponents for the National Party leadership - so far - are Simon Bridges and Amy Adams. Mr Twyford wrote both of them off as not having a chance.

"Amy doesn't really have any kind of emotional connection with people. She's got a hard edge to her. Simon Bridges, he's obviously a polarising figure - a lot of people don't like him.

"I don't know. I'm backing Judith. I think a hard, right-wing, red meat National Party, we need a right-wing party that's got the courage of its convictions - that would be Judith."

Ms Collins said she has "enough" support to win, but was coy about the numbers. There has been talk of a fourth entrant - former policeman and private security contractor Mark Mitchell, whom NZME political editor Claire Trevett earlier this week described as "likely the only politician who has shot at other people".

"I've spoken to Mark, but I certainly haven't got an indication that he's going to join the race," said Ms Collins.

National gets a taste of Labour's woes

Perhaps taking Mr Twyford's support with a grain of salt, Ms Collins reminded him of Labour's revolving door of leaders before Jacinda Ardern swept them to election success.

"I've blocked out those memories. Please, don't bring them back," replied Mr Twyford.

Ms Collins also said the National leadership battle wouldn't get nasty.

"The National Party's not normally big on the really nasty rough and tumble, not like the Labour Party."

Mr Twyford, having voted in a few Labour leadership elections, couldn't argue with that.

"We could run lessons - we could run a workshop."

So far, Ms Adams has the public support of MPs Maggie Barry, Chris Bishop, Nikki Kaye and Tim Macindoe. Ms Collins and Mr Bridges have not yet publicly revealed their supporters.