It is the first real contest for the Labour leadership in 16 years; the first in three decades where the outcome was not entirely predictable before the first vote was even cast. It has pitted left against right, Blairite against Brownie, even brother against brother.
Yet the five-way confrontation that activists craved after Gordon Brown's coronation in 2007 has stubbornly failed to catch fire.
It is not for want of trying: the five candidates have trooped around the country facing each other at dozens of hustings and rallies since their nominations were confirmed, but no one has landed a knockout blow, and no one has been fatally hurt.
The candidates have four more days to try to make a dramatic change in the campaign before the ballot closes on Wednesday. This time next week, Labour members will know the identity of their new leader; whether they are any more enlightened about the future of their party remains to be seen.
So, what have we learned during the leadership campaign?
1. The days of the Blair-Brown soap opera are over
Or not. The main contenders have benefited from high-profile endorsements but shed their uncomfortable associations with former leaders when it has suited them. And they have been happy to pass on the black spot to rivals: "Ed Miliband was working for Gordon when I arrived in 1993," Ed Balls told the IoS last week, "and he wrote the  manifesto.") Blair v Brown is well past its sell-by date but it lives on in its inferior spin-offs.
2. Ed Balls has run the best, shrewdest campaign
He looks like a credible opponent for David Cameron, so, naturally, he will lose. The former schools secretary has built an enviable reputation over almost two decades as Brown's chief bully-boy; deputy chancellor and general troublemaker. He could never have erased 17 years of diligent mischief in just four months, but he has had a go – and impressed with his clarity and pugnacity. The real task for the winner will not be beating Balls, but working out if they dare exclude him from the Shadow Cabinet.
3. Andy Burnham is more than a pretty face. But not much more
What can one say about the political acumen of a would-be leader who cites singing "Dirty Old Town" at his 40th birthday party as the greatest moment of his life? Three of his rivals rated the birth of their kids as their favourite experiences (David Miliband, who has two adopted children, volunteered "holding my sons for the first time"). Burnham has leaned heavily on his down-to-earth northern background, but it has failed to gain traction. Oh, and guess which he chose between playing for Everton in an FA cup final and becoming the next Labour PM ... ?
4. The party likes the idea of Ed Miliband more than it likes the man himself
In theory, Mili-E is an ad-man's dream – a Miliband who is not quite so superior. We're prepared to forgive his frequent detours into jargon, though they make him sound like a Martian making a fair stab at human language. And he does have a winning knack of making the Labour Party feel good about itself. But on careful listening, the constant references to passion, energy and other buzz-words can make him seem less weighty. If only there was a more serious Miliband out there.
5. Labour does better without a leader
The general election result was the worst in living memory, yet a Mori poll last week put the party level with the Conservatives on 37 per cent – its best showing for over two years. There is a salutary lesson somewhere: it may be that the coalition needs a focus for its counter-attacks (probable); or that Labour is now mature enough to lead itself. That sees less likely, somehow.
6. Harriet Harman is the one of the best leaders Labour never had
It's hard to see the routinely ridiculed stand-in as heiress to heavyweights Anthony Crosland or Roy Jenkins, but she has done well, with some devastating strikes at Cameron in Parliament. Which makes one wonder if she regrets not standing in the first place.
7. Diane Abbott has proved her worth
Well, she weathered public monstering by Andrew Neil, but the promised left-wing perspective has failed to materialise. Abbott did get across that she is not a white, 40-something, male, ex-New Labour minister. And she didn't back the Iraq war. But the "genuine, left-wing alternative"? Did we mention she's not a 40-something, white bloke?
8. Post-New Labour will have a clear policy stance
Up to a point. The main contenders are shuffling around on the same (centre) ground. The Milibands have an implicit disagreement between higher taxes (Ed) and decentralisation (David). Balls has made a bid for the Labour right, via his criticism of immigration policy. Burnham contends Labour should defend its record.
9. David Miliband is stuffy, aloof, geeky, nerdy – and probably the next leader
Mili-D's image-makers have done their best to make him appear more human. But, ultimately, David's twin appeals are that he appears statesmanlike and he is not any of the other candidates. Grand and other-worldly will be OK if he can match up against Cameron in Parliament.
10. The hard part starts here
With no Lib Dems, Labour is effectively the only Opposition. In a time of austerity, this offers a great opportunity to monopolise material that can embarrass the coalition and highlight its follies, but it is also a heavy responsibility. In the hope that the party is not too long from a return to power Labour's leader must impose discipline. Problem is, this may involve unpopular decisions such as supporting some government cuts. David Miliband is already havering about attending a TUC rally against the cuts; this may be the shape of things to come.