In England the question is not whether the Conservatives will win the next election but by how much. If the game is up for Labour south of the border, the same cannot be said in Scotland. That’s not to say it won’t lose seats; it most certainly will, but it will be less marked and will be predominantly to the SNP — not the Tories.

The long-hoped-for Cameron bounce is just not appearing, with polls suggesting that the Scottish Conservatives will improve only marginally on the support they managed in 2001 and 2005. Yes, this would be better than their Holyrood results, but the party always has performed better in the Westminster elections, where more of their supporters feel encouraged to vote and others see a party that can form a government as being more relevant.

In 2007 an indomitable performance by the Scottish Conservative leader Annabel Goldie was not enough to bring reward. The Scottish people wanted change and saw Alex Salmond’s SNP as being the best vehicle for it. The Tories slumped to their worst electoral defeat in living memory, falling below 14% of the vote for the first time.

And while Goldie may be a game old bird — she is competent within her policy-light limitations and has a St Trinian’s sense of humour — beyond the market of her blue-rinse brigade, she has little crossover appeal. Polling shows consistently that she cannot break above a 15% approval rating, below Wendy Alexander and significantly behind Salmond, who is now regularly above 60%.

Having settled for first minister’s questions as the extent of her job, Goldie delivers half of the work rate of her predecessor, David McLetchie, and, unsurprisingly, has little to show for it. McLetchie’s greatest triumph was to deliver the Ayr by-election win — but if such a contest were to be held now, the SNP could be expected to romp home in such a seat.

Not satisfied with her languid approach, her strategy towards Scotland is incoherent — demanding a referendum on the EU Lisbon treaty but denying one on the union that would surely wipe the smile off Salmond’s face.

Whereas Cameron harvests votes from former Labour followers, Goldie preaches to the converted on the rubber chicken circuit. Whereas Cameron challenges the perceptions of modern-day Conservatism, Goldie confirms the prejudices of old-school Tories. Whereas Cameron now leads Brown in every social class — not just the ABC1s but also the CDE2s — Goldie trails in any group you care to measure.

The Scottish Conservatives need a Cameron — and they need one before the general election. That means the current crop of MSPs, and frankly I see only two that would fit the Cameron mould of being young and dynamic enough: the deputy leader, Murdo Fraser, and the new kid on the block, Gavin Brown.

Fraser is a fine speaker with right-wing credentials, but his biggest difficulty is that twice when he had the chance, in 2006 when McLetchie resigned and in 2007 after that poor Holyrood election campaign, he decided against challenging Goldie. This suggests he will wait until she retires, a time that may be longer coming than he bargains for.

Brown looks the most promising of the new MSPs. A world student-debating champion with cherubic looks and no political baggage to undermine him, he has the ability to communicate well and appeal to both sexes and he has fewer enemies than Fraser.

Most people might say “Gavin who?” but then Cameron was practically unknown in the Tory party five years ago. And his ascent has been quite staggering.

The fact that I am unsure what Brown actually believes in reveals how suitably Cameronesque he is — it also allows him a great deal of room for manoeuvre to take the Scottish Conservatives in directions they have previously considered unthinkable.

And change they must, for what Cameron has done is not just be the emollient communicator that his party so badly needed, but he has removed so many of the negatives that prevented people from voting for them, no matter how bad Blair was.

The fact is that Cameron has gone out of his way to suggest that the Conservatives have changed, even if that leaves many of its members unsure about what they stand for any more.

That probably doesn’t matter as much to the public, who may be willing to settle for someone who sounds and looks reasonable and has a human pulse.

For most Scots the union is a means to an end — it delivers security and opportunity by sharing the risks and the advantages of working with a larger partner. That the union has endured for 300 years is not what will save it — it is what it can offer in the next 300 that will make it important for this and the next generations of Scots.

If the Scottish Conservatives see themselves as the north British party of Conservatism then they must be doomed, for all the evidence shows that the mood swing in Scotland is towards feeling more Scottish than British.

A solely British party in Scotland will fade away and die with every funeral notice in the British Legion and other institutions born in our past.

To address this, the Scottish Conservatives must fight Scotland’s corner within Britain and thus make the SNP irrelevant.

Brian Monteith is former finance spokesman for the Scottish Conservatives