Key Points:

New Zealand First leader Winston Peters has a provincial bias, with his personal support disproportionately lower in Auckland and higher in the rest of New Zealand.

He is favoured by four per cent as preferred Prime Minister in the latest Herald-DigiPoll survey, down 1.6 points.

But only 1 per cent of Auckland respondents favoured him compared with 5.6 per cent in the rest of the country. His highest polling this year was in May with 6.7 per cent.

The gender bias evident in National's support - usually greater support by men - is more even.

It has 51.4 per cent support overall, with 52.5 per cent of men supporting the party and 50 per cent of women.

Labour's overall rating is 35.7 per cent with 32.7 per cent of men supporting the party and 39 per cent of women.

National leader John Key is disproportionately favoured by Aucklanders -48 per cent compared with his overall rating of 45.5 per cent.

Helen Clark's popularity is more even with 43.1 per cent overall and 44.6 per cent by Aucklanders.

The geographic bias towards leaders is also reflected in the party vote. In Auckland 55 per cent of respondents favoured National compared with 49.4 per cent in the rest of New Zealand.

Labour is favoured by 33 per cent in Auckland, lower than its support in the rest of New Zealand of 36.5 per cent.