Newshub poll: Jacinda Ardern 'getting the benefit' of so much airtime during COVID-19 - Gerry Brownlee

Jacinda Ardern holds a distinct advantage over Judith Collins when it comes to boosting her public profile because she's the face of New Zealand's COVID-19 response, National's new deputy leader says.

Gerry Brownlee also suggested the reason the Government restarted its daily 1pm coronavirus press briefings was because Labour had begun slipping in the polls.

The comments come after the National Party was humiliated in a Newshub-Reid Research poll on Sunday night - the party falling to a disastrous 25.1 percent despite a recent change in leadership.

On Monday, Brownlee stuck to leader Collins' characterisation of the poll as a "rogue", telling Magic Talk he "[doesn't] think that poll's real".

Sunday's poll showed Labour had soared to 60.9 percent under Prime Minister Jacinda Ardern's leadership - the highest in Newshub polling history - but Brownlee says she's had the advantage of heightened media coverage in recent months.

"The Prime Minister's certainly getting the benefit of having been so prevalent in the media during the COVID-19 lockdown," he said.

"They gave up [1pm coronavirus press conferences] for a few days, and when polling showed them starting to slip back, they cut back into them again."

Asked about a cartoon published in the New Zealand Herald on Monday that was unfavourable to Collins, Brownlee said it speaks to a perception of her as "a hard nut".

The Guy Body-drawn cartoon shows Collins holding the severed head of former Labour MP Iain Lees-Galloway, who last week resigned after it was revealed he was having an affair, after having chopped it off with a sword labelled 'moral standards'.

Plunket pointed out that no such cartoon was made about Ardern after the resignation of National MP Andrew Falloon, who allegedly sent inappropriate texts to at least five women, including a teenager.

Brownlee says that's to do with how Ardern and Collins are seen very differently by the public and media - but he doesn't think that'll matter much to Kiwis affected by the financial crisis.

"There's a perception that [Ardern's] a very nice person and a bit hard done by, and Judith's a hard nut," he said. "Well if you ask me, when you're going into the kind of economic times we're facing, a smile doesn't get you too far if you don't have a job.

"You've got to have a bit of a hard-edged attitude to growing the economy - expanding the domestic economy particularly - to soak up some of those 200,000 jobs that have been lost."