HERE IN Manhattan, the real New Yorkers have abandoned the city. Taking their place is a 50,000-strong circus of Southern Baptists, Midwest small businessmen, Texan oil executives, an army of secret servicemen and possibly the odd Swift Boat Veteran for Truth. The climax for this gathering of Republicans comes on Thursday evening when George W. Bush gives the speech that could save his presidency. In the audience will be a little group of Tory MPs and party strategists. We have come to learn.

But what can an incumbent President struggling to get re-elected teach an opposition party fighting to get elected? Four years ago, at the last convention, in Philadelphia, we thought there was a lot to learn from Mr Bush. I was part of William Hague’s team that had gone to meet the Texas Governor in Austin and hear his message of “Compassionate Conservatism”. It was the first time a politician on the Right had come up with an effective response to the new Left of Clinton and Blair. Mr Bush deliberately steered clear of the obsessions of his party’s activists: abortion, gun control and Monica Lewinsky. He attacked his own congressional party in Washington for their exclusive focus on economics — he said they were “balancing the budget on the backs of the poor”, and made education his priority.

I remember watching his wife, Laura, actually give her speech in front of a real classroom of inner-city kids set up on the convention stage. Those TV images summed up his whole campaign. Here, it seemed to us, was a conservatism for the 21st century: interested in social problems, not just economic ones; concerned with the vulnerable, not just the well-off; accepting of cultural change; relaxed rather than shrill. We tried at the time to replicate some of it in the Tory party, but without much success. Perhaps the transplant was too crude; perhaps the patient didn’t yet realise it needed treatment.

Tell most Conservatives today that there are lessons to be learnt from Mr Bush and they will probably laugh. His apparent attempt to snub Michael Howard will mean he has understandably sunk lower in the estimation of many Tories. Even admirers of Mr Bush have to admit that his presidency has not lived up to the promise of his compassionate conservative campaign.

The “compassionate” policy agenda of education reform and faith-based welfare inevitably got lost in the trauma of 9/11 and Iraq. But there is not much for a conservative to admire in a record budget deficit, steel tariffs and an unreformed and unaffordable expansion of federal healthcare benefits. In place of the moderation of his campaign, he has deliberately sought out “wedge issues” such as gay marriage with which to divide opinion. The result is that American voters are as polarised as they were four years ago. For Tories looking to the Republicans to show them the new conservative dawn, it has all been rather gloomy.

Until now. For as the convention begins, we are being reminded of why Mr Bush is such an effective campaigner. For a start, there is his relentless good humour and optimism. The obituaries of Ronald Reagan reminded us what powerful political weapons these can be. Mr Bush’s tour of the swing states is called Moving America Forward. His stump speeches are all about what a bright future the country has, interspersed with jokes and self-deprecating remarks. Parties face a choice about whether to talk up their country’s future or warn it’s going to the dogs. Blue skies or black skies ahead? Mr Bush’s campaigning suggests blue skies every time. And it makes sense. No electorate wants to be told their best days are behind them.

Of course the Bush team is also brilliant at negative campaigning, but there is an important lesson here for Conservatives too. Character attacks on his opponent almost never come from the President’s own lips. They come out anonymously in TV ads or by e-mail from the campaign’s HQ in Virginia. In recent weeks, Mr Bush has gone out of his way to praise John Kerry’s record in Vietnam, even as his campaign tears it apart. For Mr Bush knows that in politics the message tells you a lot about the messenger.

Finally, and most importantly, there is the lesson about reaching out to undecided voters while still appealing to your core support — the challenge that faces every democratic politician. Behind the scenes, much of the Bush campaign is focused on turning out their core vote, particularly the four million evangelicals who didn’t vote last time. That is what issues such as gun control or gay marriage are supposed to achieve. But now the election has started, Mr Bush hardly mentions them. His speeches are all about the things the uncommitted voters are interested in: jobs, education, healthcare and security.

If you watch the convention on TV, you won’t hear the speeches by the evangelical pressure groups and moral majoritarians who now dominate the Republican Party faithful. The slots in prime-time are all filled with moderates such as John McCain and Rudy Giuliani. The keynote address has been given to the Bush-supporting Democrat senator from Georgia.

The lesson for Conservatives again is simple: enthuse your core supporters, for they are your army and you can’t assume that they have nowhere else to go; but when the wider public is watching, make sure you talk about the things they are interested in.

Watching the convention here in New York is like getting a masterclass in politics. If Bush the President has taught us little, there is still a huge amount we can learn from Bush the Candidate.

The author is MP for Tatton and Shadow Minister for Economic Affairs

Join the Debate at comment@thetimes.co.uk

Times Recommends

• In the real world, the public sector must pay
• Playing politics in a land of double Dutch
• Be like the plinth people: not set in stone