Chris Trotter's column in The Independent this week considers what might have been if Helen Clark's Piper Aztec had crashed who would succeed her? The four main candidates seem to be Cullen, Maharey, Goff, and Wilson, with Cullen likely emerging as the compromise candidate, and Labour policy continuing much as it is. But the question isn't just limited to disaster scenarios - nobody lasts forever, and Clark will move on eventually. However, it is an open question whether it will be a retirement while still in office, or following the eventual election defeat.
In each of these scenarios, the result is likely to be rather different. If Clark tries to arrange an orderly succession in office (as both John Howard and Tony Blair are rumoured to be planning in the next few years), the emphasis will be on continuity and stability, meaning that her successor would probably be someone like Cullen. But if she resigns or is rolled after losing at the polls, all bets are off. There will be a push for change, for a move away from electorally unsuccessful policies (even though a defeat may simply be due to electorally unsuccessful people, "the same tired old faces" if the government fails to renew itself) - which may initially give Goff an opportunity. But if National is still dominated by Revolutionaries and begins implementing a 90's-style radical free-market programme, there would be an obvious push to provide more left-wing policies - and more left-wing leadership - in response.
[Note that due to The Independent's lack of online archives, the above link is likely to point somewhere else within a week]