Chloe Swarbrick says race is on for Nikki Kaye's vacant Auckland Central seat

The retirement of National MP Nikki Kaye has blown the contest for Auckland Central wide open, with Green MP Chloe Swarbrick saying it's "anyone's game".

Kaye announced she was leaving the National Party on Thursday - just a day after Judith Collins stepped into the role of leader. 

In leaving the National Party Kaye also vacates her seat in Auckland Central which she has occupied since 2008.

Swarbrick says Kaye's popularity in the region cannot be overstated.

"You can't throw a stone in Auckland Central or knock on a door and not hear that Nikki Kaye was a fantastic local MP," she told Sean Plunket during his Thursday afternoon Magic Talk show.

"But there's a difference between being a great local MP - which she was - and taking that to the halls of power," she continued. 

With Kaye gone, and no hint on who her replacement may be, the race is on between Swarbrick and Labour's candidate Helen White.

Although she doesn't yet know who she will face, Swarbrick says she looks forward to finding out.

"What we have here is a situation with no incumbent and that massively changes the game," she told Plunket.

"I have no idea [who will run] but good luck to them - I'm looking forward to meeting them in the debate!" she said through laughter. 

National will not leave the electorate empty for long - NZME reports things are in motion to get another National candidate for Kaye's vacant seat "as soon as possible". 

Despite the competition, Swarbrick says she believes herself to be the best person to hold the seat - and the community says so too.

"Talking to folks there is a sense of a need for a strong progressive representative and the strategic and tactical vote is for me."

But Labour candidate White also believes she is the best person for the job, telling NZME it's apparent the community needs Labour.

"People have lost their jobs, their small businesses are on the line. They need support and that's best done by a Labour constituent MP."