New Zealand First is meeting on Monday to determine who will lead the country over the next three years.
Will it be Bill English, the experienced incumbent, or Jacinda Ardern, who's only been Opposition leader a few months?
Here's how both of them got to where they are now.
When Bill Mr English was Leader of the Opposition in 2002, National crashed to an appalling defeat - just 27 seats in Parliament.
He described it as "the worst day in my political life". Now he's the Prime Minister, National is in power and there's no way he wants another day like that.
Mr English is a veteran of many political battles, and his experience in Government is exceptional.
Mr English came to Parliament in 1990 and in 1996 was appointed a minister in Jim Bolger's Cabinet. He held several portfolios, health being the most important.
After National lost the 1999 election the caucus rolled Jenny Shipley and replaced her with Mr English, who went on to fail spectacularly in 2002.
After that election it was Mr English's turn to be rolled, by Don Brash. Under Dr Brash, National just failed in 2005 to beat Helen Clark's Labour Government and faced another three years in opposition.
By then John Key was National's rising star and in 2006 he replaced Dr Brash as leader, with Mr English as his deputy.
After National won the 2008 election Mr English became deputy Prime Minister and finance minister, positions he was to hold until Mr Key resigned in November 2016. Mr Key endorsed Mr English as his successor, and caucus chose him for the role.
Mr English ran a successful campaign, bringing National back with 56 seats, 10 more than Labour.
But it wasn't quite enough and now he waits for Winston Peters to decide whether he remains as Prime Minister or again becomes Leader of the Opposition.
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Mr English, 55, was born into a farming family in the Southland town of Lumsden, the second youngest of 12 children.
He studied commerce at university and farmed for a few years before becoming a Treasury policy analyst.
Mr English was an active National Party member and in 1990 won the Wallace electorate seat, which later became Clutha-Southland.
He became a list MP in 2014.
One word from kingmaker Winston Peters and Jacinda Ardern could leap from mid-ranked opposition MP to Prime Minister in just seven months.
The Labour leader has had a dream year in anyone's books.
In early February she was a list MP with some aspirations, but no hopes of leadership.
Her win in the Mt Albert by-election later that month set off a series of chain reactions that led her to become the party's deputy leader upon the resignation of Annette King and then leader in August when Andrew Little stood down.
She stood unchallenged with the full backing of her caucus just weeks out from what, at that point, seemed an unwinnable election.
There was 'Jacindamania', the party's polling skyrocketed and suddenly Labour was a real contender.
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But the stardust, as National leader Bill Mr English put it, did fade on election day and now it's NZ First who will determine whether Ms Ardern's fairytale political story continues right to the ninth floor of the Beehive.
Regardless of the decision it's been a big year for the 37-year-old from Morrinsville, a former Mormon and the daughter of a former police officer turned diplomat.
Ms Ardern is the second female Labour leader after Helen Clark, whose office she worked in after finishing university. She also worked for now Auckland Mayor Phil Goff and in Britain's Cabinet Office, and was president of the International Union of Socialist Youth until becoming a list MP in 2008.
She ran twice unsuccessfully against parliamentary colleague Nikki Kaye in Auckland Central in 2011 and 2014, but finally won herself an electorate when David Shearer vacated Mt Albert in February.
Ms Ardern has been Labour's children's spokesperson since 2012 and that's really where her heart lies.
When giving up other portfolios after becoming leader in August she held onto that one, saying children's issues was what got her into Parliament in the first place.
NZN / Newshub.