Guardian Essential New Zealand poll: Winston Peters in position to become election kingmaker

Latest survey sees support for New Zealand First exceed 5% for second month as Labour falters and National remains unchanged ahead of October election

Neither a Labour nor a National coalition could form a government without the support of populist minor party New Zealand First after the October election, according to the latest Guardian Essential political poll - which showed respondents unwilling to give either major party a commanding victory.

Since August, the governing Labour party slumped 2.5 points to 26.9% in the survey, which also recorded unsure voters - 5.3% in September - in its final result. But the results showed apathy towards both of the biggest parties, with centre-right National failing to pick up any speed from August, despite remaining ahead on 34.5%.