A new poll shows support for National continues to drop, but Judith Collins is the most popular Opposition leader for some time.
Despite a small fall in support, the poll shows Labour has enough support to govern alone, while the ACT Party is ahead of both NZ First and the Green Party.
The latest research by polling company UMR - conducted before the recent Covid-19 outbreak - also showed New Zealanders were feeling better about the state of the economy than they had since before the first nationwide lockdown.
UMR has long been the pollster of the Labour Party, and its polling has previously been criticised as tending to show higher support for the Left than other polls, however the document obtained by the Herald was for a poll conducted for corporate clients.
A document sent to corporate clients this week showed that a poll of more than 1100 people showed 52 per cent had indicated they would vote Labour if the election was to be held today.
While this would be enough for Labour to govern alone, it is the third consecutive monthly drop of one percentage point for the party, since it hit 55 per cent in April.
National meanwhile measured its lowest reading in the UMR series for several years, dropping 4 percentage points to 28 per cent.
Part of the loss appears to have been picked up by the Act Party, which jumped from just over 3 per cent in June to 5.9 per cent in July.
That puts Act ahead of the Green Party (5.4 per cent) and NZ First (5.1 per cent) for the first time in the UMR series for at least three years. UMR said it was Act's strongest showing in the poll since 2003.
For National there was better news in the preferred prime minister rating. While Jacinda Ardern remains by far the most popular in the series, at 61 per cent, this is a four-point drop since May.
Collins jumped from being the preferred prime minister of just 5 per cent of those polled in May to 20 per cent in July. This is the most popular an Opposition leader has been in the UMR poll since Bill English stepped down in early 2018.
The poll also generally showed New Zealanders were less concerned about their ability to pay bills than they had been over the past two months, and felt better about the economy overall.
A total of 44 per cent of voters believed economic conditions were with "excellent" or "good", up 13 points from June and the best reading since February.
This was still outnumbered by the 54 per cent of those polled who believed the economy was "not so good" or "poor", however this was a fall of 13 per cent on June. Back in May, 73 per cent of voters had negative views of the state of the economy.
The poll showed mixed feelings about easing border restrictions.
A total of 46 per cent supported allowing up to 10,000 international students to return to New Zealand subject to 14 days' quarantine, up from 39 per cent in June. Those opposed fell from 37 per cent in June to 32 per cent in July.
Meanwhile, support for a transtasman travel bubble was slipping. Only 28 per cent were in support of the bubble in July, down from 32 per cent in June. Those opposed to the travel bubble rose from 42 per cent in June to 46 per cent in July.
UMR's poll also showed strong support for charging people returning to New Zealand at least part of the costs. In July, 25 per cent of those polled believed those returning should pay all of the costs of quarantine (22 per cent in June), while 34 per cent believed they should pay half of the cost (31 per cent in June) and 24 per cent believed they should pay about a quarter of the costs (23 per cent in June).
Only 14 per cent of those polled in July believed returning New Zealanders and permanent residents should pay none of the costs of quarantine.
UMR said the survey was drawn from a nationwide omnibus survey of a "nationally representative sample of 1187 New Zealanders" aged 18 or older.
The fieldwork for the online survey was conducted between July 29 and August 3.