Internet Mana leader Laila Harre will take on Prime Minister John Key in the Helensville electorate.
Harre says she wants to debate Key at candidate meetings and says he has "some explaining to do."
Key had a 21,000 majority at the last election and has held the seat since 2002.
“I want to wake New Zealanders up from the anaesthetic trance that John Key has induced with his soothing words," Harre said.
A spokesman for Key said, "the Prime Minister has said Ms Harre is free to stand wherever she likes."
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