A campaign battle has begun in the Hutt Valley near Wellington to succeed the long-serving MP Trevor Mallard.
Mr Mallard, a Labour stalwart who has been the local MP since 1993, retires from the Hutt South seat next month to go on the party list and has been replaced as a candidate by the relative newcomer Ginny Andersen.
National candidate and list MP Chris Bishop said now was as good a time as ever for him to win. The seat has never been held by National, but over the past few elections the party has made some inroads.
In 2014, Mr Bishop lost by just 709 votes to Mr Mallard and he has been strategically campaigning for the seat since then.
He has been door-knocking every week and holding regular "catch-up with Chris" days in different parts of his electorate. It was a very easy way of meeting people, he told RNZ.
"People expect to see you out and about doing leaflets, putting up your signs, on their doors and in their shopping malls.
"Door-knocking's a really important part of it because you get to see the issues and get to hear about the issues that are important to people."
Hutt South was "growing strongly" but a growing population was putting pressure on infrastructure and housing, he said.
Labour candidate Ginny Andersen is a former police policy unit manager. She stood in the seat of Ōhāriu in 2014, losing to United Future's Peter Dunne by 710 votes.
She acknowledged how slim the margin was in Hutt South and said this time she was determined to win.
"Just getting out every day and connecting with people ... and talking to people about what affects them on a daily basis, and how they can influence their lives by voting and changing the government."
Ms Andersen has also been hitting the streets to reach as many people as she can. On a recent day in the suburb of Wainuiomata, she encountered a few mothers at home with their young children, who told her affordable housing was important to them.
She also visited the local shops and spoke to pharmacy owner Clive Cannons, who said the suburb had fallen on hard times.
"A lot of the manufacturing's gone down ... it's just like the rest of the country, they've all gone overseas," he told her. "Shopping has also changed ... our mall has died."
Six candidates are standing for election in the electorate, which is relatively diverse, with both wealthy pockets and poverty.
The other four, however, acknowledge the race is between Mr Bishop and Ms Andersen.
At a recent 'Meet the Candidates' debate in Maungaraki, attended by about 70 people, a local woman asked the pair which policies would be better for middle-income families: National's promise of tax cuts from next year, or Labour's families package.
"[Who's] going to look to my family and other families who might be earning in that $80,000-120,000 bracket with a couple of kids?"
Mr Bishop went first. "It's not a trade off between cutting taxes and public services. What we have now as a country is choices."
Ms Andersen followed. "So Labour's policy is to expand that lower to middle bracket, so expanding who is eligible for Working for Families to reach that middle."
After the meeting, the woman, who didn't want to be named, said it was good to hear from both of the candidates, but she was still undecided as to who she would vote for.
It is those swing voters that both Ms Andersen and Mr Bishop are targeting as they look towards 23 September.