It sometimes happens that people or a party struggle to find a voice. They may not lack an audience; they may have energy, eloquence and intelligence; they may have sensible measures to propose. Yet the ideas refuse stubbornly to cohere around a hard-edged impression of who they are and why they bother. We may vaguely like what we hear, and nod in agreement with individual items in the shopping basket; but something about the whole fails to convince. Awaiting reassurance, we file them under Maybe.

After two years in which it has tried hard to forge an attractive brand, and in which its competition, the Labour Government, has looked seriously tarnished, the Conservative Party and its leadership is still being filed under Maybe: and by too many floating voters for its comfort.

The situation is hardly dire. I am reasonably sure that the Tories are heading for an overall majority in a general election, whenever held. But the whole Tory team needs to move up a couple of notches in the national imagination, and knows it. Many are genuinely perplexed by their party's failure to break through.

Perplexity is compounded because the leader, David Cameron, has a high and positive profile. A strong, sure-footed and commanding character, he enjoys pretty favourable ratings in polls. And he is pitted against a Prime Minister who has led Britain into deep trouble and lacks the more obvious attributes of a charismatic leader. So why Tories ask) aren't they doing better?

I think I know. The Tory party is fighting the wrong enemy. It is fighting its old self. Its leadership has become fixated by the hammering it experienced at the hands not of the present Labour leader, but the last one. Still mesmerised by Tony Blair it has failed to notice that Mr Blair's reputation is gradually fading, his legacy in tatters, and the last thing that the British electorate wants is a return to the slick and dishonest politics of Mr Blair's new Labour Mark I, or a Prime Minister who reminds them of him.

Tony Blair hypnotised much of the younger generation of Tory MPs: so much so that they feared, still fear, and secretly admire his style. The Tories always rated Mr Blair more highly than did his own party, concluded that the best way to fight him was to emulate him, and convinced themselves that third-way politics must be the key to victory.

Perhaps that was once true; certainly the vindictive and reactionary vibes that the Conservative Party was thought to radiate needed extinguishing. But these battles have been won. Blairism is terribly 20th-century, and the Tories have failed to keep up with a changing public mood.

We reach the paradoxical position where the “modern” part of the Conservative Party is stuck in about 2001, and horribly out of date. There is no national nostalgia for a return to the decade in which, we now begin to realise, it all started to go adrift. Does the Conservative Party in 2008 not understand this?

Gordon Brown does, in his dark and bitter heart, understand. He knows what was always rotten about Blairite politics, detests it, and British voters are coming late to the same realisation. The contrast that Mr Brown presents with his predecessor - shadow where Blair was all sunlight, leaden charmlessness after the unbearable lightness of being Tony - is now his strongest selling point with voters.

That our present Prime Minister is a deranged monster of a politician has still not dawned on most people, and in the meantime Mr Brown is pulling off the remarkable feat of running more successfully against a Labour Government - the previous one - than the principal Opposition is running against his own.

There is a strong sense that we have had a change of government; and little appetite for reversion to the former one. It is unwise of the Opposition to paint a picture of itself calculated to remind us of what we lost when Tony Blair scuttled off the stage two years ago.

But my analysis is anything but bleak, for I believe there was always something unreal about “compassionate Conservatism” Mark I - it was more a marketing strategy than a manifesto - and that beneath the gloss lies a real Tory party, and a real David Cameron, that is well suited to the hour. Party and leader need only to be true to themselves and the voters will listen. Mr Cameron is nothing like Mr Blair, and never was. It's time he realised that he no longer needs to pretend to be.

This was brought home to me this week when I saw the announcement that, in seeking cuts in spending plans, a Conservative government would exempt health, schools and international development. [International Development? Britain's whole official aid programme is awash in waste. Among those who visit Afghanistan, Dfid (the department's acronym) is a byword for ill-targeted effort. Here is a bloated budget ripe for swingeing efficiency savings, and I simply do not believe that Mr Cameron and his Shadow Chancellor, George Osborne, can be unaware of this.

No, what lies behind this bizarre ring-fencing is a piece of pure political marketing. And - and this is the point - bad marketing, too. Presenting the Conservatives as the kind of party that would sacrifice higher education, transport investment and scientific research before it would touch overseas aid is positively Woodstockian in its other-worldliness. This isn't modern; it's Joan Baez, Joni Mitchell.

I offer aid only as an example; the pickings would be small. But a range of small examples would soon add up. Take (for instance) the Departments of State for Wales and Scotland. We don't need whole, separate departments. Scotland and Wales are devolved.

As I write, I can hear the counter- argument for the Opposition: “Don't give examples; don't scare the horses; don't play into Mr Brown's hands by giving him instances of ‘savage Tory cuts' to parrot.”

To this I reply that Mr Brown, too, is missing the public mood. The voters are less infantile than modern marketing strategies suppose. In straitened times people expect a responsible Opposition to search vigorously and openly for ways of saving taxpayers' money, and not to be timid or sheepish about the search. In the year ahead the public will witness cruel retrenchments in the private sector, retrenchments affecting their own lives. There could be tremendous national resentment towards a public sector cocooned against equivalent sacrifices. If the Tories seem ashamed or evasive in their approach to this, voters will ask where they really stand.

I would put Kenneth Clarke in charge of efficiency savings. And, were I David Cameron, I would lead from the front. This tougher and more severe approach is not alien to Mr Cameron's nature: arguably it is truer than the image he has so far sought. Then, all at once, the party and its message would seem to gel.

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