Act leader Don Brash is to stand in the North Shore electorate, but says he is not challenging National's candidate Maggie Barry and will instead target the party vote.
Dr Brash said he had not planned to contest any electorate, but was persuaded by Act's board to stand in North Shore to further boost the relatively strong party vote Act has enjoyed there.
He expected Ms Barry, who replaces retiring Defence Minister Wayne Mapp, would win the seat easily and said he did not want to take votes from her.
However he said many voters who would back Ms Barry in the electorate would give their party vote to Act because they supported Act's economic policies over National's.
Dr Brash has in the past lived in the electorate and has strong family ties there.