For the first time in almost 50 years the race to be Northland's next MP is wide open with polls showing New Zealand First leader Winston Peters has a real chance of breaking National's decades-old grip on the seat.
Two polls in the past week have sent shock waves through the National Party, which has long enjoyed some of the country's biggest majorities in Northland. It was won last year by Mike Sabin with a 9300-vote majority.
However, Mr Sabin's abrupt resignation earlier this year triggered a by-election which is refusing to follow the usual script, thanks largely to Mr Peters' decision just over 10 days ago to throw his hat into the ring.
Last week Wednesday Prime Minister John Key said Mr Peters had "zero chance" of winning; the following day a 3News Reid Research poll put Mr Peters on 36 per cent support, 6 points ahead of the newly named National candidate Mark Osborne. Labour's Willow-Jean Prime trailed on 16 per cent.
Uncertainty over the by-election's outcome was compounded by Sunday's Colmar Brunton poll for TVNZ's Q&A showing Mr Peters and Mr Osborne neck-and-neck on 36 per cent with Mrs Prime on 20 per cent.