David Parker has to be the front-runner for the Labour leadership. Excluding Nanaia Mahuta's capricious candidacy, Andrew Little and Grant Robertson have too narrow an appeal and are making their moves prematurely.

I met Parker when he was the right-hand man to the late Howard Paterson, then reputedly the richest man in the South Island.

A respected commercial lawyer with a good business head, Parker brought many of Paterson's far-sighted plans to fruition.

He surprised me by expressing a desire to enter Parliament as a Labour MP. A winnable list position was out of the question for the 2002 election and Parker entered via an upset win in the normally safe National seat of Otago.

Advertisement

He impressed caucus with an intelligent and persuasive analysis of the "corngate" fiasco that dominated the 2002 election campaign. He rose rapidly in the Helen Clark ministry and his integrity, intelligence and diligence led him to the deputy leadership under David Cunliffe.

Parker has a warmth and authenticity that would make him a vote-winner in an election campaign. He notices and absorbs the world around him. He once told me a clear sign of growing inequality is to be found in the state of factory workers' teeth.

He's no slouch in an argument, as his bettering of Bill English in a recent TV debate demonstrated. Although you mightn't associate "charisma" with Parker, you wouldn't associate it with Jim Bolger, either, and he won three elections in a row.

Above all, Parker understands that Labour must be the party of aspiration. He showed this in his 2014 Congress speech.

But he faces an unusual leadership election, which can produce unpredictable results.

When Labour adopted the preferential voting model for its democratised leadership elections, it probably didn't factor in the possibility of a four-way contest.

Simply put, if no candidate wins 50 per cent plus one more vote on the initial count, then the lowest-scoring candidate is excluded and that candidate's second preferences are distributed. This process continues until a candidate gets the requisite majority of 50 per cent plus one vote.

If, for example, three candidates score about the same level of support but none reaches the magic mark, then the least popular candidate's second preferences may well decide the result.

Advertisement

Thus the MPs, party members and affiliate electors have to think not only about who's best to lead a disconsolate party, but also about the possible levels of support for each contender and who's likely to come last.