Rangitikei MP Ian McKelvie said his National Party will now "get on with the job" under the leadership of Todd Muller.
Muller ousted Simon Bridges to become the party's new leader on Friday afternoon, a move that McKelvie said was "positive from a party perspective".
"I think from Simon's perspective, he was a victim of a number of very unfortunate twists in history, and I think any leader would have struggled their way through the last 18 months bearing in mind what he's had to put up with."
McKelvie said all opposition leaders around the world were "finding it hard to get their message out there" at the current point in time.
"From the party's point of view we're a strong organisation with a very strong base to us.
"We'll move on and the next few weeks will be interesting."
With only "120-odd days" till the next election, McKelvie said the National Party "had to get moving".
"I think both Simon and Todd are pretty different, and I'm sure we'll move in a different manner than we have been, but that's just life in politics."
Whanganui MP Harete Hipango said Friday had been a "challenging day".
"The decision wasn't unanimous, but it was a secret ballot so we don't know which way the numbers fall," she said.
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"I'm sure that Todd, with Nikki Kaye by his side, will be able to get the best out of people.
"Everybody has a different delivery style, but the substance of Todd's messaging is that he comes from a community, just like we all do, and it's about being on the ground maintaining the connectivity with the people.
"We don't live in ivory towers down in Wellington, and Todd is someone who exemplifies how important it is to always remember where we come from."
Hipango said the election campaign would be "invigorating".
"It's about rolling our sleeves up and getting stuck in," she said.
"I certainly acknowledge the effort Simon has put in, and he has been vilified by the public and by some parts of the media as well.
"There's a human cost to all of this, and when Jacinda Ardern speaks about being kind and compassionate, I think that should be applied to some of the judgments being thrown about towards someone who may not share your political views."