Green Party co-leader Russel Norman has thrown his hat into the ring to contest the Auckland seat of Mt Albert.
The seat was vacated after former prime minister and Labour MP Helen Clark took up a position as head of the United Nations Development Programme in New York.
Dr Norman says the fact that the Greens are putting up a co-leader as a candidate shows the party is taking the by-election seriously. He says he would move from Wellington to the Mt Albert electorate if he won the seat.
Radio New Zealand's political staff say list MP Melissa Lee is the current favourite for the National Party's candidacy, and David Shearer, a UN official based in Iraq, is tipped as the Labour frontrunner.
Labour will select its candidate for Mt Albert on 3 May. The potential candidates are: Meg Bates, Glenda Fryer, Simon Mitchell, Stuart Prossor, David Shearer, Farida Sultana, Chris Tremewan, Rhema Vaithianathan and Helen White.
The by-election will take place in June.