Winston Peters the likely kingmaker

Winston Peters could hold the balance of power on Saturday night. Photo / Andrew Warner

Prime Minister John Key has not ruled out having New Zealand First leader Winston Peters as Deputy Prime Minister after a new poll has shown minor parties enjoying a spike in popularity.

The latest 3 News-Reid Research poll conducted between September 9-15 saw National drop to 44.5 per cent, while NZ First climbed 1.2 per cent to 7.1 and the Conservatives hit their all time high of 4.9 per cent. The Greens also climbed in popularity to 14.4 per cent.

NZ First candidate for Tauranga Clayton Mitchell said the poll results and the party's position were "really exciting".

Earlier in the day, Prime Minister John Key told media he "wouldn't rule out" appointing Mr Peters as Deputy Prime Minister.

"I was just like, 'wow, that's some seriously positive words from National and for National supporters as well'," Mr Mitchell said.

He refused to be drawn on what parties NZ First might side with after the election.

"We're independent. We're not in Labour's lap. We're not in National's pocket. Our policies are the most important thing for the party," he said.

"Our caucus will decide democratically where we will go when we've got all the information after election day."

Deborah Cunliffe, Conservative Party chairwoman for the Bay of Plenty and Tauranga, was happy to see the party balancing on the five per cent threshold.

"People have decided it's time to make the new government more accountable to the people," she said.

"If it is an amalgamation of lots of little parties, so be it."

Mrs Cunliffe said she was not concerned National seemed to be losing votes to the smaller right-wing parties.

"Obviously, the people of New Zealand are saying National isn't doing what we want them to do and are turning to the minor parties."

Simon Bridges, National candidate for Tauranga, said under the MMP system, elections were always very close and this would be no exception.

"If people want a strong, stable National Government and they think they are helping National by voting for a minor party, they are not.

"A vote for a minor party will lead to instability and the economy stalling."

Mr Bridges said the Prime Minister had been clear he would prefer to work with the parties National had worked with before - Act, United Future and the Maori Party - but if it came to it he would consider working with New Zealand First or the Conservatives.

Labour candidate for Tauranga Rachel Jones said she could see no reason why the party could not work with NZ First.

"Obviously I would prefer if Labour was in a stronger position but Labour's worked with Winston in the past so there's no reason we couldn't do it again although Winston's actions are really hard to predict," she said.

Tauranga Green Party candidate Ian McLean said the party's current polling was "fabulous".

Poll results

• National 44.5% — up 2.2%.

• Labour 25.6% — down 0.5%.

• Greens 14.4% — up 1.4%.

• NZ First 7.1% — up 1.2%.

• Conservatives 4.9% — up 0.2%.

• Internet Mana 2% — up 0.3%.

- 3 News-Reid Research poll conducted between September 9-15.