A political scientist has revealed who he believes will have a good shot at becoming the new National Party leader and who he thinks has no chance.
On Tuesday morning, Todd Muller unexpectedly announced his resignation after taking time to reflect over the weekend.
He became leader in May after rolling previous leader Simon Bridges with deputy Nikki Kaye.
"The role has taken a heavy toll on me personally, and on my family, and this has become untenable from a health perspective," Muller said in a statement.
"For that reason I will be stepping down as leader effective immediately."
Political scientist Bryce Edwards told The AM Show Muller handled the Hamish Walker scandal last week "badly" and that was the turning point.
Walker stepped down as the National Party's candidate for Southland after he admitted to leaking COVID-19 patient data to the media, which was handed to him by ex-National Party president Michelle Boag.
Watch the Newshub Special on the National Party leadership crisis live tonight from 7:30pm on Newshub.co.nz.
"National had been doing quite well and rebuilding under Muller but then with the Hamish Walker debacle and then it was looking like they couldn't win the election," Edwards said.
"There's no doubt there has been immense pressure on him in the last week from colleagues, from the media. No one can handle that sort of stress and politics is a brutal game and it will take a hammering on your health and your mental wellbeing."
He said he felt bad for Muller who was "thrown in right in the midst of the very critical time for National and he couldn't handle it".
Nikki Kaye will be the acting leader until a vote occurs but Edwards said with the 2020 Election coming up in September, the National Party will now be scrambling to find a new leader.
"We haven't seen anyone declare yet but you've got to imagine that [Nikki] Kaye will be on this list, and I think Judith Collins will be talked about but her association with dirty politics will rule her out.
"Some people will be nostalgic for maybe Simon Bridges coming back but again I think this will be a backwards move.
"Amy Adams is another option."
Edwards told The AM Show he doesn't think Collins will have a good shot at the leadership due to her history.
"[Judith] Collins would be a very polarising pick, she might push the boat down," he said.
"No, I think she will appeal to a lot of the National base, that's true but she can't win over that central middle voter I don't believe. And she's too closely connected with the sort of thing that pulled National down last week."
However, former United Future leader Peter Dunne said Collins is in a good position to become leader.
"It's staunching the wound that's important... she's probably best-placed to do that," he told NZME.
Former National Party Finance Minister Steven Joyce says it's important for MPs to unite behind a single figure "who you believe will do the best job now and then shut up and get
on with it".
He told NZME that it was a "tough time" for the party and he has yet to speak to Muller or Kaye.
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