With 100 days to go until the election, anticipation is growing among MPs - and the opposition is feeling bullish about its chances.

Labour's campaign chair Kieran McAnulty said he believed the party had a genuine opportunity to make this the first one-term government under MMP.

"It hasn't happened often in New Zealand's political history, and we've got a shot," he said.

National leader Christopher Luxon said his party would spend the next 100 days setting out what was "at risk" if there was no National-led government after November.

"How do we actually get our economy growing even faster? How do we make sure we continue to restore law and order, deliver better public services?" he asked.

"Everything's boiling down to who are the best economic managers of this country and this economy."

National was on 28.7% in the most recent RNZ-Reid Research poll, but the coalition would still be able to form a government on current polling.

New Zealand First, which was on 11.5%, could return with 15 MPs based on current polling.

Leader Winston Peters grinned on his way into the House.

"Things are about to take off in the right direction. I know it's lovely news for you guys, you'll be so pleased to hear that."

Act leader David Seymour said the party was feeling great, pointing to "really big stuff" like the Arms Act and the Employment Leave Act that were going through the House this week.

The party would put forward more "good, solid, honest" policy over the next 100 days, he said.

"The Act Party may not be the biggest, we're not the loudest, we're not the newest, but boy are we unlocking New Zealand's potential."

Green Party co-leader Chlöe Swarbrick said her party would help Kiwis realise that Parliament was supposed to work for them, and would campaign "relentlessly" on affordable bills, healthy nature, and restoring honesty to politics.

"We're feeling really good about it. We've heard loud and clear that New Zealanders are frustrated with this government, they want change."

Te Pāti Māori is urging people to switch to the Māori roll so Māori can have a bigger say in how Aotearoa is run.

"The Māori roll increases our political influence, the general roll diminshes it," co-leader Rawiri Waititi said.

It made sense for Māori to aim for as many seats in Parliament as possible.

"If all Māori were on the Māori roll we'd have between 14 to 15 seats in Parliament and that's a huge influence on the political landscape here in Aotearoa."

Co-leader Debbie Ngarewa-Packer said there had been "massive changes" to the rules around elections this year and they hadn't all been well communicated to some Māori communities.

People have until August 6 to sign up for the Māori roll.