Just over a week to go in the Northcote by-election and Labour's spying an opportunity, with its internal polls signalling a tight race between the two major parties.
However, National is confident it can retain the seat vacated by the long-serving electorate MP Jonathan Coleman, who resigned six months after the 2017 general election.
Two targeted polls from Labour show its candidate, Shanan Halbert, within two points of National rival, Dan Bidois. But National said its internal polling showed a more comfortable gap of eight.
The pair are the two highest-polling candidates in the by-election, with their closest opponents the Green Party's Rebekah Juang and ACT's Stephen Berry.
Given there were 6000 votes between the two top candidate's last election, National feel safe.
Mr Bidois said the feedback he received was overwhelmingly positive.
"We've been getting out there, door knocking, going to malls, going and seeing people, and the response has been fantastic. So our goal is to translate that positive response into votes, and so that's what we're focused on.
"I think we'll come home with a very strong victory."
But Mr Halbert said the by-election was an opportunity for Northcote to get a good, local representative to Parliament.
"People were quite loyal to Dr Coleman in many respects. While they saw him as a terrible health minister, they viewed him quite positively locally because he was present.
"The difference between [Mr Bidois] and I, is I've lived here for coming up eight years now. I bought my first home here. I live and breathe our issues every day, right down to the traffic congestion on Onewa Road."
Both candidates had plans for the traffic congestion in the Northcote area.
Mr Bidois wants plans for a second harbour crossing brought forward, and to look at on-ramp connections to State Highway 1. He also wants to trial permanent clearways and more park and ride facilities.
Mr Halbert wants the sky and sea paths sorted, to give people the option of cycling into the city, and boost the area's public transport options.
Ms Ardern said the result could come down to whether people turned out to vote or not.
Northcote residents can vote for their preferred candidate up until 7pm on Saturday 9 June.