Former Tauranga National MP Bob Clarkson is moving camp and supporting the Act Party at November's general election.
Mr Clarkson, who went to Parliament from 2005-08, told the Bay of Plenty Times he will be resigning from the National Party and joining Act in the next week.
Several other long-serving National Party members in Tauranga are also considering switching, including Lloyd Christie who was the Kaimai electorate chairman for six years.
Mr Clarkson said: "I have been a (National) member as far back as I can remember; it might be 40 years. I care about New Zealand and any party that keeps the country on track financially and maintains living standards... that's the one that gets my vote."
He said when Don Brash became the Act leader it was like "a bolt out of the blue. He is promoting the policies that National had when I went into Parliament in 2005".
"It stuns me that the Government is not dealing with the debt and public sector spending.
If it was a private business with that much debt, it would have gone bankrupt. In this situation, you clamp the chequebook shut."
He said Dr Brash was on the right track when he got interest rates down, while he was Reserve Bank governor (from 1984-2002).
"Now we want him to get rid of the debt, by forcing the government to be more aggressive in dealing with the issues."
Asked if there was a revolt in his National Party ranks, present Tauranga MP Simon Bridges said: "Not at all. It's quite the reverse."
He said the Tauranga electorate had the second or third-highest number of members within the National Party in the country, and since he had been MP (in 2008) membership more than tripled.
Mr Bridges said he had not received any membership resignations, and he suggested there would be no more than a handful "as a result of actions from another political party."
Mr Clarkson helped organise Dr Brash's visit to Tauranga on Monday. Mr Clarkson arranged the advertising that drew more than 150 people to a public meeting in the evening - many in the audience were National Party members.
Mr Christie, Mr Clarkson and Bonnie Leonard, who stood in the last local body election, have formed an Act organising committee in Tauranga. A fourth member of that committee did not want to be named.
Mr Clarkson said he would not be standing as an Act candidate. A process would be taken to select the Tauranga candidate, including confirmation by the Act national executive.
He claimed at least 12 senior National Party members in Tauranga would be supporting Act. "We won't run a full blown campaign but they will form the basis of a team that lets people know what is happening and why they should vote for the Act Party."
Mr Clarkson said the disenchantment of those National Party members stemmed from the new Marine and Coastal Area Act, which restored access to the courts to seek recognition of customary title.
They opposed the bill and expressed their concerns to Mr Bridges. Instead, they wanted to maintain the "one law for all" approach.
Mr Christie said: "It's not me who's changed; it's National. They moved to the left and walked away from 'one law for all'. There's other reactions as well... such as National flying in the face of voters on the anti-smacking bill and introducing the Emissions Trading Scheme, which is very unproven in my mind."
Mr Bridges said National had a good story to tell in Tauranga.
"People I talk to acknowledge that. John Key and the government is in a tough economic space and they are doing really good getting the Budget back in order and reforming welfare and the public sector."
Mr Bridges said some members had expressed their views about the Marine and Coastal Area bill, and he does not recall being asked to vote against it.
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