Gordon Brown has a year. The odds are obviously heavily against him staying in 10 Downing Street, but there is still a range of possible election outcomes. What appears a certain result in the feverish mood now could be very different when polling occurs in May or early June next year.

Mr Brown’s short-term position is secure — unlike John Major’s in the mid-1990s. On most issues, despite Wednesday’s defeat over the Gurkhas, Labour retains a comfortable Commons majority. And yesterday, the Government at least avoided further defeats, so Mr Brown was able to claim to have achieved some reform of MPs’ expenses — even though the big issue of the second homes allowance remains unresolved.

There is also no serious prospect of a leadership challenge to Mr Brown before the election. Even his strongest Blairite enemies do not want to risk Harriet Harman succeeding him.

But Mr Brown’s underlying predicament is still clearly parlous. He has become accident prone and his battered personal authority has left most of his own MPs veering between the despairing and the fearful. And that is leaving aside the deepest recession, and the worst public finance crisis, for 70 years.

Labour is now in the danger zone in the opinion polls of being well below 30 per cent, with the Tories established above 40 per cent. In the past this has proved to be the point of no return for a governing party.

Mr Brown’s options are limited and his fate is largely out of his own hands. What can he do himself? It is hard to reverse the image of being a loser to become a winner again. Above all, Mr Brown needs to avoid deepening the hole he is already in. This means calmness and less reliance on his more frenetic, and partisan, advisers. There must, above all, be no repetition of the Damian McBride e-mails affair.

But there are no quick fixes. A limited Cabinet reshuffle is probable after what are certain to be dire local and European elections in five weeks. But such changes are unlikely to make any real difference to voters.

Labour’s only realistic hope is that Alistair Darling’s Budget forecast will turn out to be correct: that economic activity will bottom out and begin to recover towards the end of the year. However, most outside forecasts regard this as unrealistic. Labour optimists hope that voters will then accept that the Government has done its best to get Britain through a nasty period not of its own creation, and has a credible plan for recovery. There are a lot of ifs here — most at, or beyond, the bullish end of economists’ projections.

Even if Mr Darling’s optimism is justified, this may not be enough. The challenge for Mr Brown is, after a dozen years or more of a Labour Government, to provide a convincing case for a fourth term. At present, the main emphasis is on fighting the recession rather than on a recovery plan. What will replace the hole in the economy created by the contraction of the financial sector? And how will the public finances be put right? Last week’s Budget was only an interim, and flawed, response. Admittedly, the Tories do not yet have a credible answer. But the onus is on Mr Brown and the Government to have a plan for post-crash Britain.

Labour optimists look to the electoral system, which, despite boundary changes, still favours them because of the way votes are distributed. On any given share of the total vote, Labour should win more seats than the Tories.

The existence of a large third block — currently more than 90 — of Liberal Democrats, nationalists and Northern Ireland MPs also makes it harder for the Tories to win an overall majority..

If, and it is a big if, Labour can get up to the mid-30s in share of the vote, and the Conservatives are held at about 40 per cent, it is possible that no party will have an overall majority.

This list of conditions shows how the luck has to run all Mr Brown’s way over the next year just to prevent the Tories from becoming the largest single party, and probably even from winning an overall majority. Another Labour overall majority now looks a very remote possibility. Even a hung Parliament could hand the initiative to David Cameron. Yet the sheer unpredictability of politics explains why Mr Brown and his team will fight until the very end.

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