Shock reason Jacinda could lose
As far as the polls are concerned, it's a foregone conclusion. Later this evening, Labour, likely in coalition, will be deemed the winner of the New Zealand election and Jacinda Ardern will remain as prime minister.
The final TVNZ/Colmar Brunton opinion poll, released on Friday, had Labour on 46 per cent and the opposition National Party on 31 per cent.
Maybe not - there is reason for Ms Ardern to be worried. Under New Zealand's electoral system, called "Byzantine" by one critic, there is a path to victory for the opposition despite its struggle to gain traction in the polls.
It's a "long shot," a political analyst told news.com. au, but it's a long shot Ms Ardern knows all too well. After all, its circuitous path is how she, against all the odds, became PM three years ago.
Add to that the fact that voting is not compulsory, Labour's vote is edging downwards and the Greens are looking wobbly, and Ms Ardern's team would be forgiven for having a few last-minute nerves.
At the 2017 general election National, similar to Australia's Liberals, ended up with 44 per cent of the votes - tantalisingly close to a majority.
Leader Bill English was a shoo-in to continue as PM having seen off the threat from Labour which had polled just 37 per cent under leader Jacinda Ardern who had only been in the role for six weeks.
Yet it was Ms Ardern who became PM.
How this came to be lies in New Zealand's voting system. It is quite unlike Australia's, and was introduced in 1996 to upturn the two-party system and ensure smaller parties would have more clout.
For a start, its parliament only has one chamber, the House of Representatives, so there are no Senators to vote in.
Despite this, New Zealanders still get two votes as part of its mixed member proportional (MMP) voting system.
The first ballot is for the local MP. This is winner takes all vote - so long as candidate A gets just one more vote than any other candidate, they're elected. Of the 120 seats, 71 are allocated this way.
There are seven Maori electorates reserved only for people of Maori descent. You can vote in a Maori electorate or general electorate - but not both.
Critically, however, Kiwis also get to vote separately for a party that make up the rest of the seats. These "party" seats are divvied up proportionally based on how many votes each party gets.
It's this vote that really changes things as it's the best way for smaller parties to get MPs. Usually, if any one party can get more than 5 per cent of this vote they can snag a few members.
That's how the populist New Zealand First party managed to get nine MPs in the last parliament despite not winning a single electorate.
HOW ARDERN WENT FROM LOSER, TO WINNER
Undeterred by Labour's second place in 2017, Ms Ardern managed to skillfully stitch together a coalition with NZ First and a confidence and supply agreement with the Greens to give her government a slim majority.
NZ First's Winston Peters said he plumped for Labour simply to "shake up the status quo". He also became Deputy PM and Foreign Minister.
His decision left a stunned National wondering how they'd beaten Labour convincingly yet were now staring at them from the chilly wasteland of the opposition benches.
"(Ardern was) elected almost by accident," said The Australian's Greg Sheridan this week.
"Under the Byzantine protocols of her country's eccentric electoral system, though she won far fewer votes than the National government she replaced."
Ms Collins is hoping to repeat that complicated little trick in 2020.
NATIONAL'S STRATEGY TO WIN
Talking to NZ television channel Three's AM Show on Friday, the opposition leader said she could claim victory despite trailing Labour in the opinion polls.
"If we can get in the late 30s, that would be fantastic and that is a way through.
"We have got 15 per cent in (the opinion) poll last night (as) undecideds. We could do a lot."
Ms Collins said ACT, on eight per cent, would be an obvious coalition partner.
"It would be great. Let's just be realistic. If these polls are right and you have got ACT at eight. That is actually a winning combination."
Political scientist at New Zealand's Massey University Richard Shaw said it was an interesting strategy.
"It's a possibility," he told news.com.au. "But at the moment there's roughly a 10 per cent gap between Labour and National so it's a long shot."
National might also be hoping the Greens - who would almost certainly side with Labour - will poll below the crucial 5 per cent threshold in the party vote and so lose all their MPs.
In the last few polls, the Greens have got dangerously close to slipping under this level, but they're now back up at eight per cent.
Votes for parties that fall beneath the five per cent line are known as "wasted votes" and are then shared out with the other parties based on how well they do. So, if Labour do maintain their gap with the opposition that effect might be limited.
OTHER BIG CONCERN FOR ARDERN
But there's another worry in a country where there is no legal compulsion to vote - lazy Labour supporters.
"Turnout is the key here - people who do polls don't always vote, so any complacency on the part of those Labour voters could certainly cost Ardern," Professor Shaw said.
There's also the so-called "shy Tory" phenomenon, where centre right voters are embarrassed about admitting their preference to pollsters.
The nightmare scenario for Ms Ardern is that Labour voters are so convinced she'll win they don't bother to turn up to vote.
That could then narrow the gap and allow a National-ACT coalition to narrowly sweep in, tortoise and the hare style, with perhaps NZ First if they poll much better than forecast.
"I just don't believe the polls because it was wrong on Brexit, it was wrong on Trump, it was wrong on Scott Morrison," Ms Collins bullishly told website Stuff last week.
The election is hers to lose, but Ms Ardern certainly isn't taking anything for granted. On Thursday, she made the surprise admission that she would leave politics altogether if she lost the election.
Given her unexpected electoral success in 2017, Ms Ardern knows more than anyone that results in New Zealand elections may not be quite what they initially seem.
Originally published as Shock reason Jacinda could lose