John Rentoul: This isn't the start of the coup. Just the pre-convulsions...

Dial this premium-rate number if you want Jacqui Smith out of the Cabinet. Or the last digit is 2 if you want to get rid of Alistair Darling. Geoff Hoon is 3 or Hazel Blears is 4. Talk about a recall power. Why should the new fashion for mob rule stop at petitions to force MPs to fight by-elections? Why not put the whole Cabinet on prime-time ITV – I think the schedules are fairly clear this week – and let the people decide who should hold which great office of state?

The polls have not even opened for the real voting in the European Parliament and English county elections, and already the reshuffle, which was supposed to be the Prime Minister's response to the verdict of the people, has begun. That's direct democracy for you. It is what people want, isn't it?

Already, the House of Commons faces its biggest clear-out since 1945 as the skittles of the expenses fury fall. But this is not enough for some.

What people want, as I understand it, is that anyone who has done anything wrong, as judged in the court of public opinion, should stand down immediately. If they were going to go in a few months' time, they must go now.

And we want a general election. Also now. And in that general election, we want to vote for None of the Above. We certainly do not want any politicians to put themselves forward for election. We want Esther Rantzen, Martin Bell and that bloke off the telly. But we'll have Vince Cable, because he doesn't count. And we might have to have David Cameron as prime minister because who else is there? But we don't want political parties, or whips, and we want a Government of National Unity as long as it doesn't claim for any expenses.

Except that I do not believe that this is what the voters really want at all. Yet the fuss over expenses has converged on the strange way that reshuffles are conducted to make a desperate situation for Gordon Brown dangerously combustible. The problem with reshuffles is that everything seems to leak straight away. The moment that the Home Secretary confirms to the Prime Minister that she wants to step down at a reshuffle that she guesses is a few days away, we all know about it.

Junior ministers such as Beverley Hughes, not wanting to look as if they have been pushed, announce their departure before No 10 can. Openness and transparency are wonderful principles, but, as a large number of MPs realised, which was why they tried to block publication of their expenses, they can make politics awkward.

Tony Blair was often criticised for botched reshuffles, which happened usually because, once the process starts, a lot of decisions have to be made quickly before it all unravels in public. And I know I shouldn't say this, but Brown could do with a little of Blair's baser political skills now. One of the former prime minister's most useful abilities was that he could sound emphatic and clear without actually saying anything.

He would not have made the mistake that Brown made of talking of Darling's tenure as Chancellor in the past tense. Nor would Blair have made the slip of the tongue by which Brown described Hazel Blears's property dealings as "totally unacceptable" – a slip that has caused the Prime Minister endless trouble since he made it two weeks ago.

Brown managed his first two reshuffles pretty well. When he came in, the line-up was solid, even if Paddy Ashdown couldn't be persuaded to go to Northern Ireland. And last October the shock of Peter Mandelson's return was enough to cover the installation of Nick Brown, his lieutenant, as chief whip. But now Brown is running out of surprises. He might put Ed Balls into the Treasury, but he would need one hell of a diversion to distract people from the fact that his personal faction had taken control of the commanding heights. (And from a feeling among Labour MPs that Alistair Darling had been treated harshly.)

I still think, though, that what we are witnessing is the pre-convulsion that will depose Brown, rather than the beginnings of the coup itself. However badly Labour does in the European elections, and however messy the reshuffle becomes, the problem remains one of how to change leaders again without triggering an early general election.

I suppose that Alan Johnson – for it is most likely to be him – could say that he needs nine months to set out his stall of renewal and cheerful one-liners. (He came up with another good one last weekend, calling David Cameron and Nick Clegg the "self-righteous brothers".) But I don't think that would cut much ice with the tricoteuses of the talent-show democracy that are demanding instant gratification.

Whoever takes over from Brown would have to promise to go to the country within six months, I would have thought. So if Johnson were to take over next week – no doubt opening his first Cabinet meeting as prime minister by quoting John Major, "Well, who would have thought it?" – there would have to be an election this autumn.

Which is one of the reasons why I still think that Brown will limp on until September or October, when Johnson can promise an election in the spring. Another reason for delay is that the willingness of Labour MPs to do "whatever it takes", in Brown's own phrase, to minimise the massacre of an election is not yet clear enough. The mood of Monday's meeting of the Parliamentary Labour Party appears to have been one of confusion, depression and lashing out rather than one of regicidal purpose.

The European elections will, of course, be terrible for Labour, and, combined with expenses-driven anti-incumbent fury, are playing havoc with the opinion polls. The 18 per cent for Labour in Ipsos MORI's poll this week cut Labour MPs deep – fully five points below Michael Foot's worst score. Foot, cherished as he was, has been the personification of unelectability in Labour history. And Brown does not even have the consolation of being cherished. The mood against him in the party will harden over the summer. The popular clamour to get him out will have to wait; and that for an election will have to wait a little longer still.

It may be argued that the desire of many Labour MPs – including many that have already said that they will stand down when the election comes – to prolong their stay is an unworthy one. Well, their motive is irrelevant: they are quite justified in not wanting a general election now. The rules of the game are clear. MPs are elected for five years. So long as there is a majority for the Government, it has not so much a democratic right but a democratic duty to carry on. It would be quite wrong to short-circuit the constitution just because a minority of MPs are thought to have behaved dishonourably in claiming expenses.

British government is not a talent show where trivial errors are punished with permanent despatch to the outer darkness within hours. If this is how democracy is supposed to work, I'm checking in to the Priory.

John Rentoul is the chief political commentator for The Independent on Sunday. His blog is at www.independent.co.uk/jrentoul