Well, that's that. So long and thanks for all the fish, David.



Not since National leader Don Brash walked the plank in 2005 has there ever been such defining imagery of a political leader's demise. David Shearer punctuated the end of his 20-month leadership poignantly with two sweating, flaccid snapper.



Tuesday's Question Time - in which he was completely owned by a triumphant John Key - was the last gasp in a Labour experiment that went horribly wrong.



In many ways, Shearer and Brash shared a common downward trajectory. There was an initial wave of optimism centred around the anti-politician. But it soon gave way to shambling television appearances, a lack of PR nous, poor judgement and memory lapses.



Neither left office of their own volition. Brash was driven out by The Hollow Men book, Shearer by a restless caucus.



What followed was John Key - National's Antaeus, thus far invincible and undefeated in the political arena.



Whoever, the next Labour leader is, they face a Herculean task.



Even buoyed with the direction and fresh vision of a new leader, it will be a long hard slog to get the party and caucus soothed, unified and campaign-ready.



And if they do get there in the next year, they will have to match - and better - the remarkable energy shown by Key in election campaigns.



There is no stand-out contender that could win an election tomorrow. The best Labour can hope for is a capable leader-deputy combination.



Should David Cunliffe win, he will have to unpick the nasty in-house PR campaign that has lead much of the country to believe he is a villainous pariah.



In his favour, he's awfully good with numbers, and the polls show voters are still primarily concerned with the economy.



Grant Robertson will have to overcome the image that he is a Beltway policy wonk who would be a fish out of of water in the provincial heartlands.



With either man, the party no longer has anything to fear from election debates - both are more than a match for Key, quick witted, confident and with a masterful command of detail.



There are other names popping up in the commentariat. Andrew Little is a promising talent with strong union support - but still a first term MP who hasn't yet won a seat. Shane Jones has impeccable Maori and Pacific connections, but is known to be indolent. He also has about as much appeal to women as sex-texter Anthony Weiner.



Robertson and Cunliffe are the only real options, and both solidly left. With the New Lynn MP's grasp of finance, and Robertson's hold on health, education and state service issues, if either of them were to set ambition aside and plump for the deputy ticket, it could be a formidable team.