The choice of venue was deliberately provocative. One Tree Hill was the site of a Maori pa (fortified village), and it was once crowned by a totara, a native tree sacred to the Maoris. The totara was felled by the Europeans in 1876 and replaced with a pine, now leaning at a perilous angle after a recent attack on it by chainsaw-wielding Maori activists.
In tactics reminiscent of those employed by Pauline Hanson's One Nation party in Australia last year, ACT has waged an unashamedly populist campaign for votes in tomorrow's general election. It is demanding a 10-year time limit for the settlement of land claims, and also wants a 20 per cent flat tax rate, harsher prison sentences and a clampdown on welfare "scroungers".
While the party is not openly racist in the manner of One Nation, which opposed immigration and Aboriginal land rights, its message has struck a chord with disaffected blue-collar and rural New Zealanders. Opinion polls suggest that its share of the vote has risen to 10 per cent, from 6 per cent at the 1993 election. As the prospective coalition partner of Jenny Shipley's ruling National Party, ACT politicians will be given cabinet posts if the Nationals win the most seats tomorrow.
With Helen Clark's Labour Party 10 points ahead in a poll in today's New Zealand Herald, that scenario looks unlikely. However, ACT - which uses resonant phrases such as "One Country" - is poised to send up to 15 MPs to the 120-seat parliament in Wellington.
It is the party's anti-Maori platform that has proved most divisive in a country that prides itself on good race relations. One Labour MP, David Jacobs, accused ACT of being fascist and warned that a National-ACT government would lead to "blood on the streets".
At an ACT rally in central Auckland yesterday, attended by elderly people and businessmen, plus a scattering of shaven-headed thugs, many of the speeches were drowned out by chanting demonstrators. Mr Prebble, nicknamed "Mad Dog", taunted the protesters, telling one: "Madam, help is on its way. We are going to find you a job. Yes, you're going to enjoy working. I know it will be a new experience."
ACT has tapped a vein of racism in New Zealand by attacking the "grievance industry" of claims made under the 1840 Treaty of Waitangi, in which Maori tribes ceded sovereignty to the British Crown in exchange for the rights and privileges of becoming British subjects. A tribunal set up 10 years ago to process compensation claims has become a focus for the frustrations of white New Zealanders who resent what they regard as hand- outs to the Maoris.
The demand for a time limit, while unpopular with most Maoris, is relatively mild. ACT knows that the race card must be played with caution in New Zealand, where most people regard themselves as fundamentally fair-minded. Race relations are far better than in neighbouring Australia, not least because Maoris make up 15 per cent of the population and are well integrated.
ACT was founded by Sir Roger Douglas, architect of New Zealand's radical economic agenda of the Eighties, and Mr Prebble was a minister in the Labour government that implemented it. Speaking at ACT's campaign office, which is located in a seedy area of Auckland full of strip bars and massage parlours, Mr Prebble shrugged off the racist label.
"People make those sorts of statements because they're not willing to debate," he said. "We have had the courage to raise the issues that the other parties have run away from."