This story was published on May 21, before Muller was voted new leader of the National Party.
Jacinda Ardern's opponent at September's election will become known tomorrow, when New Zealand's National party holds a leadership ballot between incumbent Simon Bridges and challenger Todd Muller.
Momentum is growing behind Mr Muller, the party's agriculture spokesperson, who has rallied support in the wake of a poll published on Monday.
National was the first-choice party of just 31 per cent of Kiwis, down from 44 per cent at the 2017 election and at the last poll, taken in February.
February's poll had National leading Ms Ardern's Labour by a point.
Then came Covid-19, which has flipped the political dynamic on its head, putting Ms Ardern in control just four months from the election.
Yesterday, Mr Muller requested a party-room ballot for the leadership, which Mr Bridges accepted and brought forward to tomorrow at 12 noon local time.
National is a conservative party in politics and nature; supporters from either camp weren't willing to speak publicly to AAP.
But Mr Muller's impressive CV gives some in the National party room hope the 51-year-old could inspire a revival of electoral fortunes.
As a staffer to former prime minister Jim Bolger, he turned down the chance to enter parliament in his 30s and instead worked in two iconic New Zealand industries; kiwifruit and dairy, with giant Fonterra.
Fonterra chief executive Miles Hurrell declined to endorse Mr Muller in an earnings briefing on Thursday, saying "we don't make any comments on what happens in Wellington".
Another industry insider spoke on condition of anonymity.
"He was a chief executive of Apata, he led a 400-strong blue collar workforce with a $50 million turnover," they said.
"At Fonterra he emerged as a leader ... I remember people saying 'who's Todd Muller?'
"He had an ability to bring together board directors, the farmer co-op shareholders, iwi, community leaders and get along well with all of them."
After that success, Mr Muller entered parliament in 2014.
In Wellington, his stand-out achievement to date was as climate change spokesperson, handling negotiations to a point where National - with a diversity of views on climate science - supported the government's Zero Carbon Bill.
"In this moment of economic crisis, we need someone with depth of business experience and networks and an understanding on how to get the best out of a team," one MP told AAP.
"Todd is proven on all those levels.
"There's a strong mandate for change and there's a lot of people in the National Party who strongly believe Todd has what it takes to be a great National prime minister."
Whether Mr Muller gets that chance will depend on tomorrow's vote of 55 National MPs.