So could New Labour really be in power for several more decades?

The genius of Blair has always been that he is utterly ruthless in his pursuit of votes across the centre ground

Ministers are supposed to say things because they are helpful to the party, not because they are interesting and true. Thus Hazel Blears has just hurt her chances of promotion to the Cabinet by confusing commentary and propaganda. "It is possible that Labour can govern for decades, not merely years," she wrote in the New Labour journal Progress this week.

Ministers are supposed to say things because they are helpful to the party, not because they are interesting and true. Thus Hazel Blears has just hurt her chances of promotion to the Cabinet by confusing commentary and propaganda. "It is possible that Labour can govern for decades, not merely years," she wrote in the New Labour journal Progress this week.

It is possible, although it probably won't happen. What she no doubt meant to say was that it is thanks to the inspired leadership of Chairman Blair that such a possibility can even be considered in the privacy of our left-leaning hearts. It may be undemocratic and arrogant for her to say so in public - but she has a point.

The genius of Tony Blair is that he has always been utterly ruthless in his pursuit of votes across the centre ground. His party, and many of his supporters beyond the party, have tolerated the approach, but they have never really warmed to it. I remember the shocked comment of a Labour member in the Dudley West by-election in December 1994, soon after Blair became leader. She did not like what was going on at all. Some of the people who were coming over to Labour, she declared, were "Tories".

Right from the beginning, there were people in his party who assumed that New Labour was just a marketing ploy to win an election and then do what the party wanted to do. "It's worse than you think," Blair tried to tell them in his first conference speech as leader. "I actually believe in it." Ever since, there have been siren voices urging him: You are safe now. We can afford to engage in a bit of red-blooded socialism. Besides, it would motivate the party's core support, which you cannot afford to alienate forever.

To which Blair's answer is the same as that of James Carville, the legendary hero of the 1992 Clinton campaign which was New Labour's template: "Whenever I hear a campaign talk about a need to energise its base, that's a campaign that is going down the toilet." The Prime Minister phrased it more decorously, but the gist was the same when he told his Labour audience last Saturday: "Above all, we must never concede any ground back to our opponents."

Nor will he. Blair's tactic is always, always to hold the centre ground and push the Conservatives to the right. The Tories tried to fight back with what is known as the Letwin strategy. Oliver Letwin is a very clever man for someone who let a burglar into his house when he answered the door in his pyjamas and believed a story about needing the toilet. His speech in February this year setting out the spending plans of a Conservative government was clever and right.

It was a response to the Portillo strategy that failed so badly at the last election. That consisted of promising large tax cuts without a remotely plausible answer to the obvious question: where would the money be saved? After an unhappy struggle under Iain Duncan Smith, Michael Howard finally did the logical thing. If you don't know the answer, change the question. The Letwin strategy consists of matching Labour's spending plans on health and schools for the foreseeable future, and holding out only the distant prospect of tax cuts. It is a mirror image of the New Labour strategy of 1997, which was to match Tory spending restraint for two years and only then get on with a moderate and circumscribed version of the party's "natural" programme.

Given that the instincts of the typical British voter are finely balanced between wanting lower taxes and better public services, there is no good reason why the pendulum shouldn't swing back in the Tories' favour at some point. What really holds the Conservatives back is the imagery of their party's past, a free association that runs something like poll tax, extremism, divided, privatisation, cuts, high interest rates, mortgage repossessions. Just as, for most of its 18 years out of power, Labour was held back by the connotations of the winter of discontent.

Michael Portillo, although he was a lousy Shadow Chancellor, is right about that. Until the party undergoes some form of dramatic and public conversion, it will not shake off its past. As he pointed out last weekend, taking his lesson from the bible of New Labour as handed down through the prophet Clinton, "A party that loses has to tell the voters that they were right to reject it. It must change. It is the change that permits the electorate to give it another chance."

Yet there is no sign that the Tory party under Howard understands this. Letwin's tax and spending plans are regarded with irritation by most of the Tory party in parliament, let alone outside. Shadow ministers outside the protected compound of the NHS and schools are furious at not being allowed to promise higher spending

The party has gone through a series of opinion polling companies because it did not want to hear what it was being told. I understand that Maurice Saatchi, the party's joint chairman, dismissed concerns about the slanted wording of a survey question by saying he wanted to make a party political broadcast out of the findings.

For all his past glories as an adviser to Margaret Thatcher, this is not the Clinton-Blair way. That is to force the party to face electoral reality and make a deep, genuine and convincing adjustment to it. It is too easy to dismiss what Clinton did and Blair does as "triangulation", as if it were simply a matter of plotting the middle position on any issue between one's own party and the opposition. As long as the Tories don't get it, Tony Blair, or Gordon Brown if he succeeds him, can go on for at least as long as the Tories did in the 1980s and 1990s.

There is, however, one complicating factor. Charles Kennedy is one of many MPs who have packed Bill Clinton's tediously heavyweight memoirs for his holiday reading. His recent speeches have been interesting, suggesting that he, too, has been giving some thought to his party's positioning. Currently, his emphasis is on the "liberal" rather than the "social democrat" part of his hybrid party's inheritance.

That is a peculiarly British form of triangulation, aiming to unite the anti-war, civil libertarian left with conservatives who are genuinely suspicious of big government. Unfortunately for Kennedy, it is undermined by a position on public services that is well to the left of the spectrum, high tax, high spending and statist in delivery.

But the Liberal Democrats' real calculation is far cruder. It is that, with a larger bloc of MPs than at an any time since 1931, a bloc that could be 60-strong at the next election, the chances of a hung parliament are good if the Conservatives ever do recover.

Then the question becomes one that the Conservatives have barely begun to consider: would they offer Kennedy or his successor electoral reform as the price of a Con-Lib coalition? Or would Labour, which has already flirted with the Roy Jenkins "bit more proportional than what we've got at the moment" voting system, be better placed to do the deal? In which case Hazel Blears may yet be a Cabinet minister in a perpetual Lib-Lab coalition government.

j.rentoul@independent.co.uk