The election could see some parties welcoming far more MPs into Parliament. They may celebrate, but sudden party growth has its own pitfalls to avoid.
It is a situation the party has been in before, having dropped from nine MPs to just two after the 2005 election, it grew again the following year to five MPs under Rodney Hide.
Parties that fractured after sudden growth
ACT is not the first to experience sudden growth. The projected increase from one to eight MPs is a mirror of United Future's in the 2002 election.
Victoria University of Wellington political analyst Bryce Edwards says the party's leader Peter Dunne was not prepared.
"There is that problem of having a significant amount of growth in a surge, bringing in ... a much bigger caucus with a party not being used to dealing with lots of MPs that have power, have their own agendas and suddenly want to do things and feel empowered."
"Peter Dunne did not have control over his colleagues. The party apparatus was too weak to deal with these new MPs as well ... suddenly he had all those colleagues who were mostly from a Christian background and that didn't work out too well and the party basically split and I think Peter Dunne didn't really know what he'd got himself into."
He says the introduction of MMP in 1996 brought two other examples: New Zealand First went from two to 17 MPs and the Alliance went from two to 13.
The Alliance - which was in opposition and had been formed by the combination of four smaller parties - had the Greens split off at the following election.
NZ First went into a coalition with the National Party but also split apart just two years into the term after National leader Jenny Shipley, who had ousted Jim Bolger, sacked Peters from Cabinet. Peters dissolved the coalition but not all his MPs were willing to join him.
Dr Edwards says there are different ways of dealing with this problem.
"If you look at a party like New Zealand First they've mostly dealt with it by taking a top-down heavy approach. So Winston Peters has had a large amount of control and he's made sure that the elected officials, the staff are always loyal to him."
Perhaps that shows Peters learning from past mistakes, but as Edwards says, "even with that, that hasn't always been enough".
Peters has been a big advocate of the so-called waka-jumping legislation, which ensures that when list MPs leave their party - which is what voters under MMP are voting for - they must give up their seat.
"That will be the friend of David Seymour, that piece of legislation, even though he ironically opposed it. So that might help keep ACT together," Dr Edwards says.
How long it lasts is up for debate however, with a member's bill to repeal it introduced by National's David Carter - and contentiously supported by the Greens - due before a select committee after this year's election.
Peter Dunne's tips for handling growth
Peter Dunne speaks from experience when he says the important thing for Seymour is to be able to weld his MPs together into a team, "pretty much from the beginning".
"You get a lot of people who've been elected for the first time, they think the world is their oyster - all those sorts of things - they've come with an objective in mind," Dunne says. "You've then got to take all those individual objectives and say 'well, actually here's what the team's about, this is what we stand for, this is what we're going to do, this is what our purpose is'."
Tip 1: Restructure
The first step is to look at the way the party's structured, Dunne says. Pick a whip, identify spokespeople and select committee responsibilities, and get to work on that immediately. Then it's location, location, location.
"All of their MPs will be entitled to have a taxpayer funded electorate office ... they'll need to work out - because they'll probably all be list MPs - where they want to locate those offices, and you probably want to be quite strategic about that."
He says it makes sense to place people where their support is strongest or where they want to build on it, rather than just where the MPs live.
Tip 2: Be at home as well as the House
Once MPs have a location, they need to make a point of visiting and being in the community. That sounds disruptive, but Dunne warns there is more disruption to handle too.
"The likely new MPs, they need to be starting to think now - not grand and loftily but thinking about what it's gonna mean for them in terms of lifestyle, expectation, commitment and all that sort of thing so that they're not shellshocked when they arrive."
He says the MPs' families need to be kept in the loop too.
"Husbands and wives and partners are suddenly going to discover that their particular person is not going to be around home as much as they were previously. It's very important to get that side of the house, if you like, in order so that you've got support there and people don't feel torn between their parliamentary responsibilities and their private responsibilities."
Tip 3: Party time
Dunne says forming a social bond is also a good idea.
"A team of eight or nine, it's a quite a manageable group to get together for dinner every now and then just to sort of not talk politics but talk other events so you form friendships as well as professional relationships and that helps tie you more closely together."
Tip 4: No surprises
He also advises being prepared for the unexpected by implementing a no surprises policy, right at the beginning of the first caucus meeting.
"There will be things that will crop up that you may not be aware of about some of your new colleagues that they may not have thought to tell you or may not have thought were important but others going digging for dirt will find," he says.
"I ran a system where I asked all my MPs to make any such disclosure to me and it was kept in confidence ... it was just so if something blew up, if an accusation was made, I wasn't completely blindsided by it, I can at least say 'yes, we're aware of that and it's not like it's being described', or 'we've dealt with that' or whatever rather than 'it's all news to me'.
Tip 5: Member management
Dunne says the wider party also needs to be more careful.
"There'll be more resources available to them in the Parliamentary sense to be able to supplement their broader party activity but on the other hand the party members - I don't mean the MPs but the party members at large - are going to have to realise that they've now got more party MPs in Parliament.
"It's not going to be as easy to sort of go off on tangents as it might have been previously when you were just ... a one person MP party and others could go and do their own thing and basically not get into trouble."
Can ACT handle the pressure?
Dunne says ACT - should it achieve the numbers the polls are projecting - is going to need much more discipline to keep the brand looking tight and coherent.
"The common cause has got to be the programme that ACT stood on for the election so that's their manifesto, that's what they've got to promote. The danger is of course that others will go off message and do their own thing."
Dr Edwards agrees, but says ACT has been around for a while and has a stable history.
"I don't think they've got lots of newcomers that have flooded into the party, they're relatively tested ... they've got proper procedures in place that I think in ACT mean that the people that are in the top 10 in the list are quite well vetted, are quite well known in the party already ... I don't think there's going to be any big surprises internally."
He warns there will be factions however, and David Seymour will have to keep egos in check.
"He'll have to keep those factions working together and these will be rookie MPs who will need to learn how to play the game - and hopefully for David Seymour they won't be too ambitious and ready to make big steps before they've learnt how to crawl.
"And of course he has brought people into the party list that have come in with a guns rights or gun ownership background and they may not fit entirely so cleanly with some of ACT's more classical liberal approach on economics."
Dunne agrees that the need to unite behind a common cause is potentially the biggest area of risk, but says being in opposition is a help to parties that find themselves growing rapidly.
"When you're in government or a government support party - as we were - you just simply can't afford any mistakes, and that creates its own problem because sometimes you've got to do things very quickly and often not explain to people why they've been done in the way that they have been."
A warning for Labour
That will not be a comfort to the Labour Party, as Dr Edwards and Dunne both point out that larger parties are not immune to the same risks.
While Labour is already a larger political machine, it is also projected to see a big increase in MPs - from 46 to 62 seats on the most recent poll's numbers.
"It's a problem in all parties that get a big influx of members unexpectedly," Dunne says.
"If the Labour Party gets a huge number of new MPs at this election, it's going to face the same sorts of issues ... making sure that they stay on message and don't detract from what the government as a whole is doing."
Dr Edwards says it is about power.
"Power gives new politicians this idea that they want to do things and suddenly it's not so much about the party, it's about themselves ... these politicians quickly forget that it's the party that the people have voted for and not those individual MPs, so they'll need a reminder of that I think."
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