Women starting to turn away from Labour

Labour's previously huge support among women has dived in the latest Herald-DigiPoll survey.

Overall the party's support fell seven points - leaving National with a four-point lead.

But the support from women has fallen nearly 10 points, from 51 per cent a month ago to 41.9 per cent - a drop of 18 per cent.

The poll suggests that Labour is still supported by a larger proportion of women than National: 41.9 per cent for Labour, 36 per cent for National, 9.8 per cent for New Zealand First and 4.7 per cent for the Greens.

The Maori Party is disproportionately supported by women and Act is disproportionately supported by men.

The number of men supporting Labour has fallen by 10.4 per cent.

Of all male decided voters who were polled, 44.2 per cent backed National, 30.8 per cent backed Labour, and 13.6 per cent backed New Zealand First.

A breakdown of the age groups sees National rating highest among 18- to 24-year-olds, Labour higher in the age groups above that to age 65.

But among those aged over 65, 38.3 per cent support National, 35.6 per cent Labour and 19.5 per cent New Zealand First.

On a geographic breakdown, the poll shows Labour with marginally higher support than National among Aucklanders - 38.9 per cent compared with 36.9 per cent.

The parties with unusually high and low polling in Auckland compared to their overall polling are New Zealand First and the Greens.

New Zealand First has 15.7 per cent support in Auckland compared with 11.8 overall.

And the Greens muster only 1.5 per cent of Auckland support compared with 4 per cent overall.

One reason for New Zealand First's relative popularity in Auckland may be its immigration policy, but leader Winston Peters did not want to comment.

Greens co-leader Rod Donald said he knew of no obvious reason his party would be polling so much worse in Auckland than the rest of the country but conceded that its image in the country's motorway capital could be a factor.

"If the reason is because of the public's perception of our transport policy, then we need to do a much better job explaining to Aucklanders that we are the only party that has serious solutions to their congestion problems," Mr Donald said.

"Building more motorways is not going to solve the problem in the long term. With oil hitting US$60 a barrel today, the writing is on the wall that if we don't move rapidly to fast, efficient and affordable public transport, only the very wealthy will be able to afford to drive on the motorways."

It is the second consecutive Herald-DigiPoll survey that has the Greens failing to meet the 5 per cent threshold.

So unless the party secures an electorate seat, it will not be part of the next Parliament.

Mr Donald said the polls had had the Greens fluctuating between 3 and 8 per cent and he was confident the party would make the threshold.