The issue of the Labour leadership has not gone away; it has become more acute. It seems obvious that the Labour Party ought to change its leader, indeed it ought to have done so already. This is not just because of opinion polls, though the polls are disastrous.

The public has lost confidence in the Prime Minister, because they think that he has lost his grip on events. There is, as far as I know, no example of a Prime Minister who has been able to recover from Gordon Brown’s position; indeed there are very few who have reached such a dire situation.

Mr Brown has not only lost the confidence of the voters, he has lost the confidence of his own MPs. The Labour Party faces the risk of its worst defeat since 1931, yet Labour MPs still refuse to take the necessary action to change their leader. One can say of the Conservatives that if they were in such a situation, they would have changed their leader at least twice by now.

One can wonder who is opposing a leadership challenge and why. It does look like Lord Mandelson’s handiwork. Perhaps he wants to keep Mr Brown in office until the final ratification of the Lisbon treaty; perhaps he gives his highest priority to making Tony Blair president of Europe.

Labour cannot reasonably expect to win the next general election, whatever Labour MPs decide to do; things are too far gone for that. But that does not mean there is nothing left to fight for, even now. The polls make it about equally likely that there will be a Conservative landslide or that the Conservative gains will be contained. A Labour victory in 2010 would be an astonishing reversal, but a hung Parliament, with the Conservatives as the largest party, is entirely conceivable as an outcome. Indeed the next general election is already on a tipping point at which a small shift in opinion, one way or the other, would produce a large switch in seats.

The most recent opinion poll was yesterday’s YouGov in The Sunday Times. It places the Conservatives ahead, with 41 per cent, Labour second with 30 per cent, the Liberal Democrats on 17 per cent and other parties, including the Nationalists, on 12 per cent. This should be good enough for a Tory victory.

The Sunday Times also publishes the judgment of two election experts, Colin Rallings and Michael Thrasher: “With polls predicting the Tories will get 42 per cent of the vote and factoring in boundary changes, the Conservative Party’s seats would rise from 195 to 371.” The Tories would need 325 seats to have an overall majority in 2010.

However, if one looks at Rallings and Thrasher’s Media Guide to the New Parliamentary Constituencies, one can see how small a swing might decide the election result. If one takes Labour’s baseline as 30 per cent of the votes, then the Conservatives would face a hung Parliament if they only got 40 per cent, but would have an overall majority if they won 41 per cent.

A single percentage point in the actual voting would be worth 14 seats, or 28 seats in terms of the majority. With the polls as they are, a comfortable Conservative majority and a hung Parliament can be regarded as next door to each other, and as about equally likely.

This may explain why there has been so much recent interest in the possibility of a hung Parliament. David Owen has written about the possibility in The Times and Alex Salmond made it a central point in last week’s conference speech to the Scottish National Party. Salmond argues that a hung Parliament at Westminster could give valuable bargaining power to Scotland, and has urged his troops to win 20 seats at the next general election.

This sheds a different light on Labour’s leadership question. If a change of leader were only worth a single percentage point in the share of votes at the next election, that could be worth 28 seats on the majority. That would not keep Labour in power, but it could result in a hung Parliament and prevent the Conservatives gaining an overall majority. If Harriet Harman or one of the Milibands could create the faintest ripple of additional support, that could be vital for the parliamentary arithmetic of the next decade. That is worth playing for.

Of course, there are hung Parliaments and hung Parliaments. On the current polling figures, the likelihood of a hung Parliament in 2010 is quite high, but it would probably be a Parliament in which the Tories were the largest party. If one looks at recent Parliaments of this kind, they have not lasted long. Indeed the typical narrow Parliament in these circumstances has usually been one in which there was a small majority, too small to last a full term. That was the character of Harold Wilson’s short Parliament of 1964.

The parties themselves must already be considering the possibilities of a short Parliament. They have not been uncommon in the past. Since 1945, there have been 17 parliaments, of which three were short Parliaments. These were the Parliaments of 1950-51, of 1964-66 and the first Parliament of 1974. In each case the main political issue of the short Parliament was a struggle to prepare for a second general election.

After 1950, an exhausted Labour Government held on to office, but failed to win the 1951 election. After Harold Wilson’s victory in 1964, he was able to win a bigger majority in 1966, and after defeating Ted Heath in the first election of 1974, Wilson defeated him again in the second.

The Conservatives at present have the momentum. That in itself could be decisive. It does sometimes take two general elections to establish a new government in power. If he found himself in the position of Churchill in 1951, or Wilson in 1964 or 74, David Cameron would have to convert his try into the goal of office. It is momentum that carries the incoming party to victory at a second election. The election of 2010 will be very important, but a second election in 2011 might prove even more historic.

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