John Rentoul: We can dabble in parallel universes, but in the real one it's all over for Gordon Brown

Towards the end of the year, normal routines are disrupted, and parents end up watching films about armoured bears with complicated plots that involve parallel universes and daemons. Then it becomes difficult to remember whether we are in the parallel universe or the other one.

Because in one universe there is an armoured bear called Gordon Brown, who has a Moral Compass, and in the other there is an organisation that resembles the Roman Catholic Church, which restricts civil liberties to impose its beliefs on people, and which has just recruited a former prime minister. Or something.

So it is hardly surprising that it is difficult to answer, during this artificial pause in politics, the one question that is on every politician's mind: Can Brown turn it round? There is an air of unreality that inspires caution in assessing a turbulent year at this time of sudden tranquillity. Gordon Brown, having endured an improbable sequence of repeated blows over the past three months, is like a boxer who doesn't know whether the fact that his opponent has stopped hitting him means that he is winning or that he is about to be finally floored.

No wonder many people take the safe option of saying, "Don't write Gordon off". But my argument is that those people are living in a parallel universe and that in the real world it is all over for the Prime Minister. I won't list everything that has gone wrong since the turning point of the year, which was not 27 June, which we all thought it would be, but 1 October.

The roll-call of embarrassments for the Government has been set out for you many times already, and will be again in this weekend's reviews of the year. But they all started with George Osborne's clever speech to the Tory conference promising to squeeze foreign private equity partners to cut inheritance tax, to which Brown responded by calling off the election that he dearly wanted to have.

Most of the other things that have gone wrong weren't his fault, but crucially he managed to make it look as if they were. In his last news conference of the year, he managed to avoid citing the most tedious clich about politics, namely Harold Wilson's "week is a long time", only to settle on the second most tedious. He said: "Harold Macmillan once said that it was events that determined how people saw you. I actually think he wasn't quite right. I think it is how you respond to events." It was a brave attempt to change the terms of the debate, but simply drew attention to the prevailing opinion that he has not responded well. If Northern Rock, for example, had happened before 27 June, Tony Blair would have implied that it was all technical economics that he expected the Chancellor to understand. "Can't you see I'm saving the world?"

At this point, the bet-hedgers talk of Brown's toughness, of his having seen off all-comers over 13 years to make the top job his. Give him time, they say, and his experience will or may tell. But this is to confuse resilience with agility. We do not need a resumption of "events" after the Christmas break to know that the game is up. Brown the armoured bear has been in the wars now, and does not look as imposing as he did at the half-way point of the year.

You do not need to have seen the film of Philip Pullman's fantasy to know that Brown looks like the usurper Ragnar who is losing the fight. Bits of his armour are coming off and the Big Clunking Paw has not turned out to be much use. So far has Brown fallen that even John Major, a moth-eaten bear who knows what certain defeat smells like, is not scared of him. He went on television recently to accuse Brown, quite unfairly, of "sleaze". He must know that all Labour's dodging of its own rules of open party funding happened on Blair's watch and yet he never dared come out and poke the one who defeated him in an election.

On his own, Major does not amount to much. However disappointing Brown has been, I would never rate him lower as a prime minister than his predecessor-but-one. But Major is like a pointer on Lyra's alethiometer, the "golden compass" of the film that always tells the truth. For his first three months as Prime Minister, Brown possessed an unseen force that drew symbolically important people to him. Margaret Thatcher came to tea. Norman Tebbit purred his approval. Admiral West, Sir Mark Malloch Brown and Sir Digby Jones entered the tent. Quentin Davies defected while Shirley Williams and Patrick Mercer pretended to.

For the last three months, however, the unseen force has been pushing people away. Mercer suddenly decided his "advisory work" had been completed. Charles Clarke's vow of silence was broken, when he said that a "large number" of Labour MPs were "appalled" by Brown's slogan, "British jobs for British workers".

Most damagingly, perhaps, Mervyn King, the Governor of the Bank of England, was reported as saying that Brown and Alistair Darling were "unable to focus because morale throughout the government is so low". King denied it to the Treasury Select Committee, but last weekend the journalist that wrote it stood by his story and named King as its source. Nor was this just any journalist. This was Irwin Stelzer, a commentator on political economics who is a friend of Rupert Murdoch's.

None of this, of course, is conclusive about Brown's ability to turn things back. But, as Major knows, once things start going against you, they tend to keep coming. Nor is there any evidence for one of the myths that might comfort Brown's demoralised troops: that the Government tends to recover in the opinion polls as an election approaches. On the Political Betting website, Andy Cooke summarises what has happened since 1979. In the long run-up to every election since then, there has been a swing, not to the Government, but to the Conservatives. He supports my long-held contention that, even after the changes to their methods since 1992, the opinion polls continue to overstate Labour support. That means that even if Brown were able to recover from the horrors of the past three months, he faces an impossible task.

That is why the talk at Westminster, before it shut down for the recess, pondered two alternative futures. One is another change of leadership before the election. The latest idea doing the rounds among serious Labour people is that of a David Miliband-Ed Balls dream ticket (although "dream ticket" is perhaps the third most tedious political clich), with Miliband as prime minister and Balls as chancellor. The other, on which I am told one of Brown's closest associates has mused aloud, is that Labour will simply have to renew itself in opposition.

The vision of Brown as a wounded ice bear is not, therefore, just a seasonal hallucination. You would surely have to inhabit a parallel universe to believe that he will eventually prevail.

John Rentoul is chief political commentator for The Independent on Sunday