The Green Party could surpass Labour at the next election if it does not get its act together, former Green MP Sue Bradford says.
Bradford told Morning Report Labour has been taking more of a middle-ground approach to its policies.
"At this point, if Labour goes on like it is, I think that there's every chance that Greens can even potentially overtake them in terms of percentages and numbers in the House, unless Labour does get its act together and become a lot clearer about who they stand for..."
But it would always be down to the context of the election, she said.
The Green Party has never surpassed the 11.1 percent of the vote it won in 2011, and its 10.77 percent in preliminary results this time around gives it 14 MPs - equal to the record number it secured in 2011 and 2014.
It was also in opposition those years likely benefited - as it seems to have in this election - from a lower-polling Labour Party, which secured about 27.5 percent in 2011 and under 25 percent in 2014.
"The problem for Labour is this focus group politics," Bradford said.
"Where is the leadership for Labour that would take the party in a much clear direction, are they even sure about who their voter base is even more?"
Bradford thought it was "very likely" Greens would get another seat after the special votes were counted.
"Given that they've won an extra two electorate seats, it's pretty amazing and I can understand why they're so excited and energised by the result on Saturday night.
"They've come a long way despite the problems of making that huge mistake which I think they made by going into an agreement with Labour over the last turn."
Special votes do tend to favour the left, but there have been suggestions this trend may not hold for this election - particularly with many of the early votes strongly leaning to the right.
With the Greens having barely scraped their 14th MP in on the preliminary results, the special votes would need to heavily favour the party to bring in another.
Bradford said the Greens would have done better this election had they stayed in opposition.
"Because it only showed up how weak they were [being in government but not Cabinet] ... I think they've learnt a really good lesson, actually running more two tick campaigns and if they do that in future, actually having a belief in their candidates and mobilising people on the ground."
She said when she was in the party, from 1999- 2009, they were very reluctant to run more than one two ticks campaign - campaigning for a candidate and a seat rather than just a seat.
They have much clearer policies now, she said.
"I think there's every chance that if they do things right they could grow the party over the next three years.
"The other side of the equation of course is what happens to Labour, whether they learn anything because over and over again they keep making the same mistake. Well, first they had Rogernomics, but since then of just going into the middle ground ... and that's got them in this place where they're simply managing for capital, for big business and big agriculture interests.
"Thinking about their traditional base - of no and low income working people, unemployed people - back in the '30s Labour was the champion, but now in full power they couldn't even reform the welfare system."
Bradford said the Greens would have done better this election had they stayed in opposition.
"Because it only showed up how weak they were [being in government but not Cabinet] ... I think they've learnt a really good lesson, actually running more two tick campaigns and if they do that in future, actually having a belief in their candidates and mobilising people on the ground."
She said when she was in the party, from 1999- 2009, they were very reluctant to run more than one two ticks campaign - campaigning for a candidate and a seat rather than just a seat.
They have much clearer policies now, she said.
"I think there's every chance that if they do things right they could grow the party over the next three years.
"The other side of the equation of course is what happens to Labour, whether they learn anything because over and over again they keep making the same mistake. Well, first they had Rogernomics, but since then of just going into the middle ground ... and that's got them in this place where they're simply managing for capital, for big business and big agriculture interests.
"Thinking about their traditional base - of no and low income working people, unemployed people - back in the '30s Labour was the champion, but now in full power they couldn't even reform the welfare system."
Bradford said the Greens "make a fine partner" with Te Pāti Māori.
"And I really have to pay tribute to James Shaw and Marama Davidson. As you know I've been quite critical of the Green Party in the last few years at times but I think James Shaw got such a shock when that strange leadership situation happened for him and he lost the confidence."
There had been a shift towards listening to party members, she said.
The Labour Party declined to comment further.
RN