The oldest, cheapest trick in party politics tends also to be the most effective. Nothing subtle, nothing of which organised crime or religious cultists would be ashamed. Simply this: do you really want the other lot? For New Labour, that inquiry-cum-challenge has worked like a charm for many a queasy year.

It works on trade unionists still hoping to squeeze a little credibility from "this great movement of ours". It works on commentators fiddling with that tricky moral compass, the people who can tell themselves (and you) that there is always enough room on the head of a pin for a tax credit botch, a PFI deal, a hospital and a hedge fund scam.

It works, always, on local government, despite the evidence of brutal experience. It works on the voluntary sector, with no alternatives worth the name. It works best, best of all, on MPs, MSPs and the entire coterie culture of ideas and careers. Sometimes it even works on voters. Seriously: do you really want the other lot?

As Gordon Brown wades through his latest crisis, that cheap trick is in danger of becoming an entire strategy for government. Its flaw is simple: Labour has been in power for a very long time. Memories of the Thatcher years, if they exist, are dim or anecdotal. David Cameron does not seem, meanwhile, to be actually infernal. He is not pretending to cut taxes or slash spending. This is the Harold Macmillan of his generation. Yet Mr Brown appears - quite a trick - to be both demonic and dull.

The economy, meanwhile, is exploring the lower reaches of the plumbing. Competence, best friend of Prudence, is no longer the Prime Minister's answer to every question. No-one appears to remember the Tories; no-one is grateful for a decade of stability and cheap credit; no-one wonders how things would have seemed had Blair remained. So: do you really want the other lot?

Opinion, however formed, is not equipped to deal with the question. Current polls are inconclusive. One for The Guardian reports that, despite everything, an election held tomorrow would produce nothing more than a hung parliament and Nationalists with the balance - for what purpose? - of power. Others suggest that Mr Brown could be gone "within days" if he cannot persuade Labour to end its traditional habit of defeating itself.

I wonder. I wonder, first, about the extent to which actually existing reality would change if Mr Brown left by one door and Mr Cameron entered by another. Happy days for banks, hedge funds, non-doms and private equity? They've had those. In fact, they left their residue on the toilet wall.

Ever since John Smith launched a "prawn cocktail offensive" in City boardrooms, unfettered turbo- capitalism has been free of haunting spectres, and of Labour's rhetoric.

Public spending cuts, then? Mr Cameron and the over-priced wallpaper heir, George Osborne, insist on their Old Etonian honour that the HenHaitchHess would be safe with them. I doubt it, but I also doubt that Edinburgh's Royal Infirmary, procured through Mr Brown's socialism-with-a-smiley-face, is viable for the next generation. The other lot could not have done better. Or - since this is what I mean - worse.

Mr Cameron says, first, that the 10% tax band would be restored; secondly, that this isn't quite what he meant. Seven billion is - according to the wallpaper heir - seven billion. Meanwhile, the Chancellor of the Exchequer tells us that he cannot "rewrite" a Budget. The tax tables are with the printers. But the memory of a Labour government rendering the less-well-off less well off is not subject, coincidentally, to revision.

Let's go for that one. Let's suggest a parallel. New Labour holds it to be axiomatic that a sensible government must never alienate the better-placed and the sensationally aspirational. Rich people are good people. So even hint that a non-dom could face a marginal tax rate of 70% and the end of civilisation might follow. Do it to the poor, however, do it to anyone who dares to earn better than £12,000, and you arrive at a different outcome. Just 5.3 million non-people who will never trust you again.

Still, they probably don't vote, so never mind. After all, their reflected resentment conjures only a mere six dozen or so Labour MPs who have had a whole year to study Mr Brown's last Budget and understand a few sums. Now the vanguard are roused, like coma victims, and passionate, reportedly. I'll believe that if they will, if they can still believe anything.

The rebellion, like the Prime Minister's chances of re-election, is a relative thing. The stalwarts put in place by a movement of working people have swallowed much worse since Thatcher fell, and all because "the other lot" were sold as a fate worse than any death. They will go on supping their condensed milk - boil up your conscience, chuck in a dash of expedience, put in a claim for the stove - until they believe the other lot are at hand.

Gordon Brown could revive his fortunes without much difficulty. It would scupper that retirement job at the World Bank. It would make a mockery of all the years spent rendering socialism safe for polite company. Still: he could just hammer the banks. Actually, properly, like he meant it.

Think of it this way. On the day that conscience-stricken Labour MPs were agitating over the 10p tax rate, on the day the Bank of England was sending £50bn of good money after bad, the Abbey chose to raise its rates. I pose a merely theoretical question: what would a socialist Prime Minister have said to that?

Try reality, instead. What should a Prime Minister who flaunts his sentiment where the least-prosperous - the many - are concerned, do when capitalism exhibits unspeakable arrogance? Bung more earned money, much of it from lower-rate tax bands, into "liquidity"? Try to "understand" the little foibles of our wealth-creators? Or act on behalf of those who gave him his career? Even Middle England would, I think, come along for that ride.

Is there an important difference between Mr Brown and the other lot? He needs us to believe it. Some, perhaps many, want to believe it. My reading of disparate polls remains the same. Come a General Election, the Prime Minister's record will survive all of Mr Cameron's actually nonsensical rhetoric. The Tories have no programme.

Paradoxically, however, Labour's plight is worse. It has no belief. When push comes to shove, you have to represent something, and any number of someones. Those head-on-pins talking heads would, meanwhile, discount an assault on the banks as rank populism.

But they would also discount the possibility that a Labour Party would be right, and justified, in doing such a thing.

Justification, and therefore justice. The haunted look on Gordon Brown's face says that he yearns, sometimes, for an inch or two of solid ground. If I possessed a religious streak, I would even say that he has sold his soul, or perhaps mortgaged same, and probably to Northern Rock. He could still redeem the debt.

My rational self says that this lot are the other lot. It adds: the banks have just taken us for a £50bn ride and we lack any means to address the fact. "Unsustainable", I think, is the word.