Act list MP John Boscawen is the leading contender to be the party's candidate in the Mt Albert byelection.
Mr Boscawen is not expected to win the seat, but will push Act's policies as well as his personal profile.
The millionaire who campaigned against the Electoral Finance Act came into
Parliament at number four on Act's list at the election.
He is now campaigning for an inquiry into the spate of finance company collapses and changes to stop it from happening again.
Mr Boscawen is likely to be named when Act reveals its candidatetoday.
He would not return calls yesterday.
There was speculation that Act would try to get rugby league coaching legend Graham Lowe to stand although he is not interested at this point.
Mr Lowe has recently turned to Act after a lifetime as a Labour voter, and is particularly supportive of its "three strikes" sentencing policy.
He visited Parliament for the first time recently as a guest of Act leader Rodney Hide and MP Sir Roger Douglas.
Mr Boscawen will join Greens co-leader Russel Norman as the second list MP in the byelection. They are set to be joined by National MP Melissa Lee, who is expected to win her party's selection contest on Monday.
Labour, which will select its candidate tomorrow, has shunned using a list MP. Its front-runner is top-ranking United Nations official David Shearer, who has returned from Baghdad to contest the nomination.
