The National party can all but write off Act as a potential coalition partner after this year's election, a Herald on Sunday-Digipoll has revealed.
The poll shows Act is facing political oblivion, with leader Rodney Hide trailing a distant third in the critical Epsom electorate.
The result means Act will have to get at least 5 per cent of the party vote if any of its MPs are to keep their jobs.
Latest polls show the party nowhere near that target, with just 10 weeks to go until the last possible election date.
Act polled just 2 per cent in a separate Fairfax-ACNielsen nationwide survey, which showed National up to 42 per cent, Labour down to 37, and NZ First on 8 per cent.
Unless the party's fortunes dramatically improve, National would almost certainly be forced to strike a deal with New Zealand First to enable it to form a government.
Just last week, Act operatives again approached former Auckland Mayor John Banks in another last-ditch effort to recruit him as a candidate, sources said. Mr Banks is understood to have rejected the offer.
Act had hoped to win the blue-ribbon Epsom seat, just in case it doesn't reach the 5 per cent threshold required under MMP.
However, the poll shows National's Richard Worth should easily win the seat, and 63.1 per cent of Epsom voters say National should not stand aside to give Act a chance.
In his first political column for the Herald on Sunday (see link below), former New Zealand party leader and property magnate Sir Bob Jones says National may yet rue its decision not to help Act. Striking a deal could have provided an extra eight MPs with which to form a government, he says.
The only good news for Mr Hide is that half the respondents believe he has done a good job, and 38.8 percent say they would vote strategically for him if it provided a partner for a centre-right government.
Mr Hide said yesterday the poll showed strategic voting would be crucial in Epsom.
The seat could make "all the difference in the world to who's in Parliament and who's in government", he said.
Dr Brash declined to discuss Mr Hide's chances.
But Mr Worth, who has been seen out knocking on Epsom doors in the rain in the past month, said he had assurances that he would not be required to stand aside for Mr Hide.
National had learned the "foolishness" of standing aside candidates after making room for United Future leader Peter Dunne in Ohariu-Belmont, only for him to ultimately support a Labour-led Government.
"Of course Act will continue to hope for that possibility, but it is utterly unreal," he said. "I see very little of Mr Hide in Epsom, and I don't see a lot of him in Parliament apart from in question time. We don't have a working relationship."
Although health is the leading election issue nationwide, one in five Epsom voters see tax cuts as key - making it the single most important issue for them.
The poll of 400 people was carried out between July 8 and July 16 and has a margin of error of plus or minus 4.9 per cent.
Prime Minister Helen Clark said through a spokesman that the Epsom poll provided further reason why voters should stick with the stability and prosperity of her Government. She believed the nationwide polling had understated Labour's support, and Labour's private polling was more encouraging.
"We remain optimistic about the election result."
- HERALD ON SUNDAYBy Jonathan Milne