The contest to replace John Key is taking shape with Auckland councillor Linda Cooper announcing her bid to be the National Party candidate in Helensville.

Key's shock resignation means the Auckland electorate will have a new MP after this year's general election.

Helensville is a safe National seat - Key had a majority of over 18,000 in 2014 - and whoever is selected by the party will likely be on their way to Parliament later this year.

Cooper, a Waitakere ward councillor, told the Herald she had long considered a tilt at Parliament and the timing was now right.

Linda Cooper wants to be National's candidate in Helensville. Photo / Jason Oxenham
Linda Cooper wants to be National's candidate in Helensville. Photo / Jason Oxenham

"This is the next level. I think there is a lot of work that can be done in central/local government relationships."

Cooper said she would stay on as a councillor through the selection and any campaigning process, but would resign if elected to Parliament.

Transport was of major concern to people in Helensville, she said.

"The North Western motorway is the only way in and out of south Rodney. We just really need to offer more transport options. The Government have already made some commitments on that, I just want to make sure it really happens.

"It is crucial to people's quality of life. They are stuck on that motorway."

Cooper also wanted to survey people in the area to see if there was demand for new schools in the area.

Another potential candidate is Genelle Bailey, who worked for Key in his Helensville office for almost 10 years. Bailey has recently put up new profile photos on her Facebook page, commenting, "here we go!". Friends have responded, wishing her luck.

Rodney local board member Cameron Brewer has ruled out seeking the nomination. He said he had given it some thought and talked to various people about a possible bid, but the timing was not right for his family, with three young children.

Meanwhile, activist Penny Bright will contest the Mt Albert byelection on February 25, on an anti-corruption platform. And the NZ People's Party, started by businessman Roshan Nauhria, will stand a candidate - Vin Tomar, an immigration adviser and former kindergarten teacher.

National is not contesting the byelection. Jacinda Ardern is Labour's candidate, and Julie Anne Genter is running for the Green Party.