New Zealand First leader Winston Peters has confirmed he will compete in the Northland by-election.
Mr Peters this afternoon said Northland needed "a real voice" who could "hit the ground running".
He said he was born in Northland, educated there, owned a home there for decades and played for sports teams in the region.
The electorate had been neglected by Government, he said, and it should be "the Florida of New Zealand".
The Northland seat was vacated by National MP Mike Sabin, who stood down last month for "personal reasons". The by-election will take place on March 28.
Mr Peters said that if he were to win, it would not change the Government but it would "change the way they think".
If he won the seat, New Zealand First would be able to gain another list MP. Mr Peters said this was not the reason he was standing.
He said his party would start as the underdog in the by-election. The Northland seat had been held by National since 1966.
But he said the resignation of Mr Sabin, reportedly because he was being investigated by police, could hurt National's vote.
Economic development minister Steven Joyce said National was "not even contemplating" Winston Peters winning the Northland by-election
"We are focusing on winning the seat. It's a strong National seat. We've got to prove it each time, but that's the nature of elections and we will be focusing on that."
Labour leader Andrew little said his party was not considering withdrawing its candidate from the by-election now that Mr Peters had announced his entry to the contest.