The Māori Party stayed on 2 per cent.
The poll of 1002 eligible voters started two days after last week's Budget and was taken between May 22 and May 26, 2021. The margin of error is +/- 3.1 per cent.
The headline item in that Budget was lifting benefit payments by up to $55 a week over the next two years as Ardern moved on her promise to try to reduce child poverty.
However, it was criticised by some for offering little to low or middle-income earners.
The poll also followed controversy about Labour's direction to limit or freeze wage increases for workers in the public sector, and National accusing the Government of a secret "segregation by stealth" agenda.
Voters continued to give a big thumbs down to National leader Judith Collins – she was on 9 per cent.
Collins' approval ratings were her worst yet on minus 19 – the difference between those who approved of her performance and those who did not. Thirty per cent said they approved while 49 per cent disapproved. Twenty per cent did not know.
However, as yet there is no obvious contender who the voters believe should replace her.
National MP Christopher Luxon had ticked up to 3 per cent and former leader Simon Bridges was at 2 per cent.
Collins told 1 News that she still enjoyed the job and it "requires real resilience and commitment". On being leader, she said she believed "that this requires the long haul".
"This is never going to be a short-term solution."
She said National's support levels were slowly rebuilding in the polls, but there was a long way to go.
Ardern said she was heartened to have the support of a large number of New Zealanders.
"I have been elected to do a job and I will keep doing that job and give it my absolute all. New Zealanders have placed huge confidence in us, and our job is to make sure we do all we can to help New Zealand recover from Covid-19."
Act leader David Seymour's stocks were on the rise: he was up two points to 6 per cent, while Green MP Chloe Swarbrick was next on 2 per cent.
A Newshub Reid Research poll 10 days ago had Labour at 52.7 per cent (up slightly on its election result) and National at 27 per cent (also up a bit).
In the preferred PM stakes, Ardern polled at 48.1 per cent (down 4.5 percentage points); Judith Collins was at 5.6 per cent (down 12.8 percentage points).
Former PM John Key was higher than Collins on 6.7 per cent, while backbench MP Christopher Luxon was on 2.4 per cent.