The left to battle it out in Mt Albert - Jacinda Ardern v Julie Anne Genter
Labour's Jacinda Ardern is backing herself to win the Mt Albert by-election and even her biggest competition, Green MP Julie Anne Genter, has accepted it's an uphill challenge.
The Green Party haven't held a seat since former co-leader Jeanette Fitzsimons won Coromandel in 1999, so Genter is well aware she's the underdog.
"I think Jacinda will be the favourite to win. She's very high profile and a strong candidate," she said.
But either way, Genter says Mt Albert voters will be "spoiled for choice" and can look forward to a by-election centred on policy debate - "not just people yelling at each other".
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Both women have successfully won the candidacy for their respective parties - while Genter has been formally selected, Ardern has to wait until next week for the final tick but in the meantime is officially the only nomination after they closed at 5pm on Thursday.
The by-election, to be held on February 25, has already been reduced to a two-horse race after National announced they wouldn't be running a candidate.
Prime Minister Bill English said it was a "safe Labour seat" and National wanted to focus its attention on the general election later in the year.
The by-election was triggered after Labour MP David Shearer vacated the seat to take a job as UN Mission Head in South Sudan - it was previously held by former Prime Minister Helen Clark.
Neither Ardern or Genter have won a seat before - Ardern has lost in the last two elections in Auckland Central to sitting MP Nikki Kaye.
Last year Labour and the Greens signed a Memorandum of Understanding (MOU) agreeing to work together to change the government in 2017.
While Mt Albert is a Labour strong-hold and Ardern is tipped to win, the Greens choosing to run a candidate of Genter's calibre signals the party won't always roll over for the sake of the MOU.
Genter says the Greens collect a quarter of the party vote in Mt Albert and it's about giving voters a choice.
"The by-election will come down to a discussion about policy - not just a war between candidates."
"I get along really well with Jacinda and I'm looking forward to working with her in government," she said.
Both women are a similar age and regularly run into each other in Auckland.
Genter's campaign is about her "selling point," which is years of experience in transport and urban design and the Greens focus on affordable housing closer to jobs.
On the other side Ardern is focusing on Mt Albert being an area in Auckland with "ever decreasing home ownership" and finding ways to overcome that.
While Ardern says her Green competition is a "great politician", she says, "you have to back yourself to win in politics".
She disputes the two parties running strong candidates is "inconsistent" with the MOU.
"We get on really well and have similarities but we also have differences and we'll be able to show an ability to work together," Ardern said.
"For me it was more surprising that National is choosing not to run a candidate than the Greens putting Julie Anne up."