The pair faced off tonight in the final leaders' debate, two days out from Election Day.
On the poll
To start the debate rolling, Ardern is asked about tonight's poll - will Labour be transformational if it gets back in Government?
"I believe we have been," Ardern responds, saying lasting changes on issues such as climate change require consensus, and pointing to child poverty as an area she says real progress is being made.
"I am not done yet."
Collins is asked about the poll numbers for National - 31 per cent. She says about 15 per cent of people are undecided, and a good number will make up their mind on election day.
The National leader says the economy will be front of mind for voters.
"There will be a lot of people who will want to say - yes, we want to come and vote National."
Asked if National should have stuck with Simon Bridges as leader, Collins said internal polling was in the mid 20s at that point.
Collins says National's path to power centres on the undecided voters, and to bring people back from the minor parties.
She said people voting New Conservative or NZ First could have their vote wasted, and if those people didn't want a Labour Government they should vote National.
There was still confusion about MMP, Collins said.
Ardern said Labour's message was clear, and the polls showed "people are looking for stability... for unity."
On the large numbers voting early, Collins said a lot of National voters would vote on election day. She hoped early voters don't get "buyer's remorse".
Ardern said a lot of people were over the election campaign, and had their minds on the future.
She said "undecided" voters in the poll could be people who have already voted, and didn't want to say who they'd supported.
On child poverty
Mutch McKay asked Ardern about poverty, and her promise to halve child poverty by 2030. The Child Poverty Action Group had said this could be fixed right now, using Covid recovery fund money.
Ardern said a big investment had been made over the past three years, including lifting minimum wage and educational and social support.
"There is urgency... we cancelled the last National Government's tax cuts in order to support those on the lowest incomes instead."
The leaders clashed over Collins' claim child poverty had worsened.
"She promised to end child poverty," Collins said. "We have 150,000 children living in poverty... it's actually just got worse."
What was Collins' target? She said National would also like to halve child poverty by 2030 but by getting people in jobs, and National had a strong track record when in Government.
"What really matters is whether or not a child is getting fed...whether they have shoes on their feet."
Mutch McKay moved on to housing. Will either leader bring in changes to bring down the price of housing?
Collins wouldn't pledge to bring down prices of existing houses, but said supply needed to increase.
"I'm not asking for people to go and lose their life savings."
Ardern said there hadn't been enough affordable houses built in New Zealand, and data showed first-home buyers now made up 25 per cent of the market, the highest proportion on record.
Mutch McKay asked: What would they say to people locked out of home ownership?
Collins said supply was key. Ardern said the deposit for first-home buyers was a hurdle, and Labour had policies to help lessen that.
Ardern cited state care for children, and the controversy over child uplifts, saying Labour had brought in changes to bring down those statistics.
Collins said inter-generational poverty and welfare dependency had to be addressed. National had done a huge number of Treaty settlements, she said.
Both leaders were slightly vague when pressed on whether new, separate systems for Māori were needed, but said innovations like Rangatahi Courts should be supported if they got results.
On the Pacific
Should a border exception be made for workers from the Pacific, to support the agriculture sector?
Ardern said that was being looked at: "Nobody wants to see fruit rot on the ground".
A question from a school student is up next - what do you have to give to New Zealand that nobody else does?
Ardern said an acute awareness that she was in the job as a privilege and not a right.
"I give my everything... even if that means a huge sacrifice."
Collins said being in Parliament was an utter privilege, and she brought 20 years' experience as a lawyer, and in small business.
"At a time of grave economic situation that we are moving into now, that is something I bring. But also the ability to make decisions," Collins said, before Mutch McKay stopped her, saying it was becoming a long list.
On the minor parties
Now the questions turns to the minor parties - will Labour implement the Greens' wealth tax?
Absolutely not, says Ardern - and suggestions that wasn't the case were "desperate and mischievous".
Collins said she believed absolutely Labour would bring it in - Ardern countered, saying it was "blatant misinformation".
Ardern asked if National would implement Act Party policies.
Collins pressed on - saying before the last election Ardern and Labour had promised they'd do certain things, and had failed to do so, including KiwiBuild and light rail to the airport.
"The Greens have extremely expensive promises they are making to their voters."
Ardern said Collins was calling her a liar, and she would never do such a thing.
What about GE technology? Collins said it was crucial to use the best science to improve productivity and address things like methane.
Ardern said that discussion should be had, and there was a way to protect New Zealand's "brand" while not losing out of improvements that could be made by GE.
On borders
What number of people should come in once the borders open?
Collins said about 50,000 a year, but housing was needed.
Ardern wouldn't give a number.
On losing
Mutch McKay asks Ardern if she loses, would she stay on as leader of the Opposition? No, Ardern says.
"Politics is the most interesting career that I have had, and I have had careers in law and business... every day I wake up... I really do have a smile on my face... it's going all day."
A last pitch to voters
Ardern addressed the undecideds - saying a vote for Labour was for strong, stable government.
It was time to look at the opportunity ahead - but that needed stability, uncertainty and a plan to take us forward.
Collins said if people wanted a National-led Government that they party vote National - for a party that understands business, with a leader who is decisive.
"Our plan is all focused on the economy... and paying down debt.
"It is really important that our children...are not saddled with debt."
Ardern spoked to media after the debate and confirmed she would stand down as leader if Labour wasn't returned to Government.
"That certainly would be my choice... our plan is to succeed on election night.
"My message would be, if people don't want to see me resign, then vote for Labour."
On the heated exchange over the Greens' wealth tax, Ardern said she welcomed the chance to be "crystal clear" that Labour would not implement that Green Party policy.
Ardern said tonight's poll showed Labour was the only party currently in a position to form a Government, and she wanted the strongest mandate possible from voters.
"I can't answer that not knowing a person... we have very few opportunities to get to know each other.
"Judith isn't someone who I know particularly well."
On the debate question about what she'd do outside of politics, Ardern said she had no plans beyond what she was doing in the here and now - and no book plans.
Labour didn't attack National over Act Party policies, Ardern said, and National raising the Greens' wealth tax was "desperate".
Post-match questions - Collins
Now it is Collins' turn to face the post-debate media scrum.
She said the debate was a different style, but a good one.
Collins reiterated that she'd stay on as National leader, if the party was in Opposition.
She defended revealing internal polling during Simon Bridges' time in leadership, saying she was asked about it during the debate.
"We never talk about the current [polls], do we."
Asked what she thought of Ardern, she said she had done well to get where she was but then quipped: "I don't know that we're going to go on holiday together."
Collins again told any voters leaning towards parties like the New Conservatives to not waste their vote, and back National.
"Every vote counts, and a party vote for National is a right vote for them."
Asked if she won the debate, she said she thought she did well, but who won was for others to judge.
Collins said she never believes polls - "the only poll I believe is election day".
Why was Act polling so highly? Collins relayed a story of one voter asking her if voting Act would help National, and that sort of confusion existed among some voters under MMP.
"They think they are being strategic.
"They are not sure - they often don't watch television or read the news on these things."
Collins said tonight's debate was her favourite of the leaders' debates.
Asked by media what the single biggest idea National wanted to put to the electorate, Collins said it was growing the economy, getting people into jobs and reducing the tax burden. And growing the technology sector.
"I want us to be the Switzerland of the Pacific, but better than that - a country where every kid gets the chance that they don't get at the moment."
Labour is on 46 per cent, down 1 percentage point, while National is on 31 per cent, also down 1. Labour would need the support of the Greens to govern, based on those numbers.
Act is steady on 8 per cent, the Greens up two points to 8 per cent, and NZ First up two points to 3 per cent.
The New Conservative Party is on 2 per cent, and TOP, Advance NZ and the Māori Party are all on 1 per cent.
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