Leadership contender Jamie Whyte says abandoning ACT for a new right wing party might look like trying to ''pull a fast one''.
Sole MP John Banks will stand down as leader in March and leave Parliament at next year's election.
He is facing trial for electoral fraud.
Whyte has put his hand up to be the party's candidate in Epsom. But there is renewed talk on the right about establishing a new party as ACT struggles to recover from a series of scandals.
Whyte, a commentator who returned from Britain three months ago, believes voters would just recognise it as ACT under a new name.
''Maybe from a marketing point of view that is the right thing to do. But in essence it would be the same party, it would have the same support base, it would have almost the same members... in a little country like New Zealand it's a bit transparent, isn't it? It may be like you are trying to pull a fast one.''
Winning Epsom is the party's last hope, he believes.
''ACT got itself in a terrible mess... it may be that if we don't get Epsom at the next election the party may kind of be over. So, it's an effort to make sure that doesn't happen.'''
Some in the party are keen for former leader Rodney Hide to make a comeback, although he is understood to have rebuffed calls to return. He did not return calls.
Whyte says he would be happy to be Hide's number two.
''Rodney is not wooden, he's not stand-offish, he's got that human quality that people relate to and... he's very smart.''
The resignation of Banks could be a fresh start, he argued.
''People in the party never thought John Banks was a proper ACT person in the first place. There are some who may instead of seeing this as another debacle may go 'great, we can start again, clean'.''
Former leader Don Brash tried to convince Whyte to stand for National in 2005. He said he was an impressive candidate, but lacks a public profile.
Party president John Boscawen wouldn't comment on individual candidates. He confirmed members of the party had approached Hide, but sensed he wasn't interested.
Other likely candidates are former president Chris Simmons and sixth ranked candidate David Seymour.
Boscawen was not taking hints by lobbyist Matthew Hooton's seriously.
''The last time I checked Matthew Hooton was a National party member. I think we are looking for an ACT person.''
Prime Minister John Key is not ruling another deal with ACT in Epsom.
''It would have to depend on two things. Who the candidate was, whether we seriously thought they could bring enough people with them, and whether it was going to work.''
WHO IS JAMIE WHYTE?
The former Cambridge philosophy lecturer turned management consultant, returned to Auckland this year after nearly five years in Britain.
He has two girls, aged 10 and six, by his Mauritania-born second wife.
A political commentator, Whyte has written four books: Bad Thoughts A Load of Blair, Free Thoughts and Quack Policy espousing free market theories.
In 1999 he worked at a consultancy with Labour leader David Cunliffe.
''We had several political disagreements,'' he said.
Last year he wrote an article for the Wall Street Journal, defending comic Jimmy Carr who was accused of reducing his tax liability through an avoidance scheme.
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