A potentially huge increase in postal voting has prompted warnings a failure to properly prepare could lead to an election disaster.
Postal votes could potentially explode and number in the hundreds of thousands because of Covid-19 if the elderly and those vulnerable because of health conditions cannot physically go to public polling booths.
There are fears of an electoral crisis if the number of postal votes outstrips the ability of government agencies to handle them.
There are acknowledged risks around both the capacity to deal with a flood of postal votes and the security of posting a ballot, rather than voting at a polling booth.
Justice Minister Andrew Little says the Electoral Commission is preparing for postal voting to play a "much bigger role than has been in the past". Rough estimates for last election were 10,000 to 15,000 but now they're preparing for up to 750,000; the "estimate of potentially vulnerable people".
There is a heightened risk, he concedes, "once you significantly expand the postal voting option", that was weighed up against "making sure that people had a sense of safety when they were casting their vote".
And in a situation where the virus could make more people feel unsafe about going to a polling booth, Little says he "trusts the advice of the Electoral Commission on the steps they take to reduce that, to minimise that."
The 750,000 figure covers the people whose voting may be affected during a lockdown; for example the elderly and those with health conditions. If there was a regional lockdown those numbers would change accordingly, depending on where it was.
New Zealand First leader Winston Peters says he became "seriously concerned" about postal voting after the 2018 census: "Everybody knows it was an absolute disaster at both the online level and the postal level... now, we're contemplating that around an election, you can see the potential disaster we face."
A major problem, he says, was votes not being processed quickly enough by NZ Post to make it on time to become a valid vote, deficiencies New Zealand cannot afford to have repeated in a general election.
And that was before Covid-19, says Peters, which creates even more alarming challenges - concerns he raised in his 14 August letter to Prime Minister Jacinda Ardern urging her to delay the original 19 September election date.
"The potential for change that's generated by a fear of leaving your home, forced to go to the postal system, and then realising how many and how few post boxes there are," he told RNZ, "which means that they will be lining up at the central post offices and again the contact and the spread will be a great danger to them," and could just lead to people deciding not to vote.
A confidential August briefing paper Effect of Covid-19 on the delivery of a General Election, from the Electoral Commission to Little, says there are "capacity limits to the number of postal votes the Commission can process" as voters may be "less willing to go to a voting place or even use a post box".
It concludes that "may decrease voter turnout".
National Party leader Judith Collins agrees there's a risk of "a deluge of votes" coming in by post, "either late or just not even being processed".
"The Electoral Commission, I think, is trying to deal with a lot of moving parts," she says, "because they don't know quite what the situation the country's going to be in".
Capacity and Security
Chief Electoral Officer Alicia Wright says the August advice about capacity limits was based on holding an election under complete lockdown and where postal voting would need to be rolled out to all voters.
They are preparing for postal votes in the "tens of thousands", peaking at 380,000, but could scale up if necessary.
Wright also says they're looking at ways to encourage people to use different options; for example they'll be offering those in rest homes a "takeaway" vote, where someone comes and collects their ballot paper.
Collins says her concerns are around the ability of NZ Post to get the ballot papers delivered quickly, as it "doesn't deliver nearly as frequently as it used to, and doesn't expect to get mail delivered from one end of the country to another as quickly as it used to... so there are real issues with that".
Wright says ballot papers posted will be treated separately to the rest of the mail, "in such a way that they are identified and we can move them through in a way that keeps them secure".
Little says the rules around verifying a registered voter have been relaxed to make it easier to use postal voting.
Someone in their own home would still need a witness, he says, but those in managed isolation or quarantine facilities would not.
Little says concerns about postal voting have been flagged in recent months and Cabinet has responded, but in the end it's up to the Electoral Commission "to run the election in a way that has integrity and that is critical, and we provided the regulatory change and the budget to enable them to do that".
"But we go on the advice and the advice is that in order to maximise turnout in these sorts of conditions, then this is something they need to have up their sleeve," he says.
He acknowledges the increased risks around security of voting by post rather than by ballot box, but assures voters that has been addressed: "We've been well advised about that and have taken steps to mitigate any risk around all of that.
"In the end, I'm totally confident that the Electoral Commission is focused on running an election that maximises turnout and has full public confidence."
NZ Post chief executive David Walsh declined an interview but in a statement says they're "working closely" with the Electoral Commission, including how it will work if some or all of the country is in lockdown.
He says currently postal voting is just for those "vulnerable" voters, and NZ Post is not set up for "mass" postal voting.
Voters who may need to use a postal or a special vote are encouraged to register in plenty of time, explore options like "takeaway" votes as an alternative, and if using the post make sure to send it off leaving plenty of time before election day.
The politics
Peters brushes off the suggestion he's worried about postal voting as it has the potential to impact an important voting base for New Zealand First - the elderly.
"One could take that narrow view," he says, "but one has to have the bigger view, and that is the quality of our democracy.
"This is far bigger than one political party ... the first duty of a Member of Parliament is just that, that we are here as Members of Parliament before we are members of political parties."
In the United States President Donald Trump has stoked fears about the risk of electoral fraud posed by postal voting - prompting accusations he's trying to undermine the election.
Little says concerns about postal voting here were well traversed by Cabinet and MPs have certain responsibilities when talking about the election: "We all want our general election to be credible and and for people to have confidence in it and for it to have integrity.
"For those who are involved in making decisions, particularly in the regulations, covering our elections, it's incumbent on us to speak in a way that maintains public confidence in our electoral process."
Collins says her concerns are about practical considerations and not about laying the groundwork to later question the legitimacy of the outcome of the election.
"They're concerns the Electoral Commission's heard so many times... every message I'm giving is if people need to postal vote, they need to contact the Electoral Commission early on."
She says National is "happy to accept" the election result, but warns Electoral Commission has a tough job ahead.