"We don't want to be like the bloody People's Front of Judea [Monty Python's Life of Brian] or whatever it is and splitting off. It's bad enough already.
"So I have no intention of hijacking the party and ramming a radical libertarian agenda down its throat."
He said he did not take drugs, other than alcohol.
Dr Whyte was of the view that there are many things he would not do, but that other people should be permitted to do them.
"I think smacking is one of them. You are criminalising an activity that is extremely widespread and that many ordinary people consider to be harmless, in fact many of them consider it to be virtuous. It is a dangerous extension of the law."
He said there was an almost manic idea right through the political spectrum that everything was a proper subject of legislation "and that society can be protected by endless legislative meddling in our affairs".
"I don't believe that."
Dr Whyte is a Kiwi who was raised in the eastern suburbs of Auckland and has returned to live in New Zealand from Britain. He was educated at Pakuranga College (where he was taught by Colin Craig's father), Auckland University, and Cambridge University and now lives in Herne Bay.
He is up against former MP and president John Boscawen for the vacancy created by John Banks, who has been committed to trial on electoral donation charges.
The decision on the leadership will be made by the Act board on Sunday.
A former philosophy academic, Dr Whyte has written books and columns and worked as a management consultant. He argued in the Times in 2006 that bigotry, not concern for welfare, explained the illegality of drug use. He said he adhered to the principle that "something is good for you if its benefits exceed its costs. Otherwise it is bad for you".
"Drug users are simply people for whom the pleasure outweighs the risk of death, illness, addiction and all the rest ... the same is not true of everyone."
Dr Whyte put the Act membership at between 500 and 1000 members with one MP, in contrast to 1999 and 2002 when it polled enough under Richard Prebble to get nine MPs.
He believes he has what it takes to resurrect the party into something it once was.
"People have just got to believe that it isn't just a vehicle for either careerist politicians or to be used by other parties for their goals - that it is more than that. It really is a party in its own right with strong principles."
Dr Whyte is 48. He and his second wife, Zainab, have two daughters aged 10 and 6.
The rival: John Boscawen
Party president John Boscawen put his name into the ring after failing to persuade former leader Rodney Hide to seek the leadership.
Mr Boscawen has been a long-term party activist and donor. Before being elected as an MP in 2008, he led and funded a campaign against Labour's Electoral Finance Bill.
While he was an MP he stood in the Mt Albert byelection and it was while he was speaking in one of the byelection debates that someone put a lamington on his head, which he ignored.
Mr Boscawen earned a reputation as a dedicated and driven MP without personal rancour.
During his one term in Parliament, the party continued to suffer from factional infighting between Rodney Hide on one side and Heather Roy and Sir Roger Douglas on the other. Eventually, Mr Hide was deposed in the caucus by forces outside the party, former National leader Don Brash as Act leader outside Parliament and John Banks as heir apparent as Epsom candidate.
Mr Boscawen became Dr Brash's deputy in Parliament and he remained a minister outside Cabinet. He retired at the 2011 election, returning to business.
He believes the party leader should also be the Epsom candidate, sending the signal that the party is offering the electorate its best.
"I think we can freshen the image of the party by taking it back to its core values of promoting the things we stood for when the party was first launched: its reforms to social welfare, education and superannuation."
He believed the party needed the fresh faces of Dr Whyte and Epsom hopeful David Seymour, but believes they have a better chance of being elected under his strategy of combining experience and new faces "which is a safer option for the Act Party".