But if you look through the current Cabinet, who are the other alternatives? If we assume that Brown goes after an election defeat we can rule out Jack Straw. Alan Johnson has already ruled himself out. The only other serious contenders I can see would be...
Jacqui Smith - if she retains her seat and becomes a serious player
Hilary Benn - a safety first option
James Purnell - if he plays things right
If I were a Labour MP I'd be thinking of John Denham. Articulate, moderate, safe pair of hands, possibly a bit dull, but competent. And that's what the Labour Party may need after an election defeat.
But I think even Labour supporters will look at the current Cabinet and view it as extremely weak. Compare it to Jim Callaghan's Cabinet in 1979 when it was possible to identify at least eight or nine serious contenders to take over from him. Brown's task now should be to promote talent from the Minister of State level. The trouble is there isn't much. Liam Byrne, Tony McNulty, Jim Knight, Ben Bradshaw, Phil Woolas, Pat McFadden, Mike O'Brien, Caroline Flint, Rosie Winterton, Yvette Cooper, John Healey Margaret Hodge, Paul Goggins, Bill Rammell, Ian Pearson... I can only identify about four who would make half decent Cabinet ministers - and none who would be able to compete for the top job.
Compare this with the top rank of the Conservative Shadow Cabinet. Fraser Nelson was rather cutting in his article, where he said...
I think that's unfair. I've just gone through the same process and easily got into double figures! And no, I'm not going to name those I would dispatch. Man for man, woman for woman, I reckon that for the first time in a decade the Tories outmatch their Labour opponents. Forget your party political hat and go down the list and give them each marks out of ten, and you'll see what I mean...
David Cameron has meanwhile been going back to his constituency and preparing for government. This has involved a fairly sober assessment of how many genuinely Cabinet-grade people he has on his team (he struggled to get into double digits). Ideally, his next reshuffle should be the last. It is vital for his prospects that the Tory frontbench look and sound like a competent government-in-waiting in comparison to the disintegrating Brown Cabinet.
Brown v Cameron
Miliband v Hague
Smith v Davis
Browne v Fox
Darling v Osborne
Denham v Willetts
Balls v Gove
And so on. See what I mean? The issue for some senior Conservatives (are you listening Ken Clarke?) is whether they wish to serve in the next Tory government (don't those words sound great, now that they no longer provoke guffaws of laughter?). If they do, they'd better make it clear to David Cameron before the next reshuffle, because if they don't agree to do some legwork before the next election, David Cameron will have to ignore whatever claims to office they may have.