This is partly because of the universal perception that politicians rarely say what they think, never give clear answers to direct questions and seldom do what they promise. But there is a more fundamental point too: three voters in five and nearly three quarters of floating voters think that “there isn’t much difference between the parties any more”. Polls asking voters to place the parties on the political spectrum find that Labour — once ineluctably left-wing — is now seen as firmly right of centre. The Tories face an unenviable paradox: much of what they say sounds indistinct from Labour, yet the deep-seated negative perception of an unchanged Tory brand means voters view them as furthest from the mainstream, far to the right. This is the Tories’ strategic problem.

The view has long been widespread among commentators that Tony Blair is unusual: not exactly a Tory, but somewhere much closer to a continental Christian Democrat than a typical Labour Party product. James Callaghan reportedly said of him: “I don’t know what that young man is, but, whatever he is, it isn’t Labour.”

The perception has grown over the years that Mr Blair, actually, is a Conservative — or, to be precise, a neo-conservative. He backed a Republican President in an unpopular pre-emptive war. He is pro-American in a party whose deepest instinct is the opposite. The international leaders with whom he has bonded are all from the Right. His public service agenda is, increasingly, market based: he introduced university tuition fees and push es the boundaries of independent management and private finance within the NHS and schools. On crime and terrorism he scorns liberal sensibilities. With the euro indefinitely parked, there is even a shade of euroscepticism in the Prime Minister’s plans to modernise EU institutions, reform its budget and scrap the CAP.

A few days before the 1997 landslide, Robert Harris noted the vast breadth of the coalition lining up in support of Labour and wondered how so many people of such different viewpoints could all see in Mr Blair something they liked. “Which of us”, Harris wondered, “will be the first to be disappointed?” By 2004 his answer was clear: “If Blair had a faction,” he wrote, “it would not be on the left at all, but located somewhere deep in the heart of the Conservative Party.”

The perception that Mr Blair has re-positioned Labour on the centre-right is at the root of the feeling that there is little clear water between the two biggest parties. It is also why so many dyed-in-the-wool Labour supporters didn’t vote in the general election.

Many Conservatives are frustrated to the point of paralysis at what feels the profound unfairness of being crowded out of their own territory by a party whose move to the right they regard as skin deep, littered with jarring inconsistencies and unlikely to outlast Mr Blair. Significantly, Conservatives are the only group of voters who do not regard Labour as right of centre. Tories occupy an alternative reality in which Labour hasn’t much changed, and where they can stick by old, safe arguments; living in denial, they avoid facing the magnitude of their problem, but are also left profoundly confused about what the case is for their ideas.

In the cause of trying to contrive meaningful differences with Mr Blair, the Tories have opposed policies which, intellectually, they should support, while adopting inconsistent tactical postures. The frustrated search for territory beyond the Blairite shadow took the Tory election campaign to the wasteland of HIV testing for immigrants, strict quotas for asylum-seekers and a crackdown on gypsies, while saying little about the economy, hospitals or schools.

The effect is that two thirds of voters think the Conservatives “just attack the Government over whatever happens to be in the news and never say anything positive” while more than half damningly conclude simply that the Conservatives “don’t seem to stand for anything any more”.

When Mr Blair became Labour leader, the first instinct of many Tories, groping for an anti-Labour narrative, was the Coca-Cola strategy: the proposition that though Mr Blair was “stealing Conservative clothes” he was not “the real thing”. To middle Britain that was the whole point: Mr Blair embodied the residual reassurance of the Conservatives without being one. It says much about their incoherence that the Tories adopted a strategy resting on precisely the opposite argument: that new Labour meant “new danger”. Unable to stop Mr Blair’s march into their heartlands, the Conservatives tried to demonise him. They failed, and Mr Blair’s revolution has marginalised the Tories for more than a decade. But his departure will not relieve them of the need to come to terms with it.

Seventy per cent of Labour voters say they regard themselves as “supporters of new Labour not old Labour”, a point unlikely to be lost on Gordon Brown. Tories pray that he will turn Labour leftward. But more than two thirds of voters think that “Labour has really changed from what it was like in the past and won’t go back to old Labour even when Tony Blair goes”. And even if a Brown premiership did tack slightly to the left, voters feeling it is time for a change are liable to conclude that Labour led by Mr Brown, not the Conservatives, represents, in the short term at least, the safest, most compelling option.

The author is a director of Populus, pollsters for The Times

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