David Davis, the long-time frontrunner, was under pressure to produce the speech of his life today as even his own supporters admitted that the performances of Mr Clarke and Mr Cameron had given them hope of winning if they get through to the final nationwide ballot.

Mr Davis is virtually assured of reaching the run-off because of the strength of his support among MPs.

But his backers conceded that he would have a fight on his hands when the contest moves to the party‘s 300,000 members this month. The result of their nationwide ballot will be declared on December 6.

Mr Davis is being urged privately to drop the “safety-first” approach that has characterised the opening of his campaign, which supporters believe has almost been forced upon him by the knowledge that he is so far ahead among the MPs.

Friends of Mr Davis said that Mr Clarke and Mr Cameron had shown in their different ways — Mr Cameron with a visionary speech aimed at inspiring a new generation of Conservatives and Mr Clarke with a vintage assault on Labour — how they could enthuse the membership. They accepted that Mr Davis would have to respond.

Some of Mr Davis’s strong backers hope that he can win 100 MPs to his side after the early ballots to send an unmistakable signal to the members that he is their runaway choice. Like most of the other candidates Mr Davis has already begun his campaign to woo the membership with a team of volunteers telephoning councillors and activists.

Mr Davis and Liam Fox, the Shadow Foreign Secretary, are the last of the contenders to make their appeals to the conference today.

The Shadow Home Secretary will tell members that the party’s goal is “power — but power with a moral purpose”.

Emphasising his belief that the Conservatives must stand up for all sections of society, he will say: “For us, government is a means. It is not an end in itself. It is a means to liberate those locked into dependence, to enfranchise those whose voice goes unheard and to empower those who cannot fight back.”

Mr Davis plans to tell the Conservatives to “walk tall, stop apologising and get on with the job”.

Dr Fox will define his territory clearly to the right of Mr Clarke and Mr Cameron by rejecting the modernising agenda. In contrast to a series of speeches from “modernising” MPs, he will tell the conference that he believes there is nothing fundamentally wrong with the party.

He is expected to add: “We seem to have this debate about how to make us more electable.

“Surely politics cannot just be about telling people what they want to hear.

“When I was a doctor, I had to tell the truth about a patient’s condition . . . We have to do the same to our country.”

But last night in Blackpool the atmosphere was still buzzing over the bravura performances by the oldest and youngest candidates in the leadership field. Mr Clarke, peppering his speech with jokes, suggested that he was a “bigger beast” even than Tony Blair and Gordon Brown. He said that Mr Brown’s legacy as Chancellor would haunt him when he succeeded Mr Blair as Prime Minister. “I will make sure of that,” he said.

He attacked the way new Labour had undermined the health of democracy, abandoned the processes of Cabinet government and treated Parliament with indifference and contempt. “Much of our problem as a party is that people do not trust us. It is not that they do not trust us because we are Conservatives. They do not trust us because we are politicians.”

Mr Cameron, 38, called on the party to have the courage to change its culture and identity to match voters’ aspirations.The Shadow Education Secretary said that people should “feel good about being Conservatives again . . . I want to switch on a whole new generation to the Conservative Party”.

He added that the Tories must admit they had failed and failed against an unpopular and mistrusted government. “As this week in Blackpool we put failure behind us, we put defeat behind us, we must look ourselves in the eye and make this pledge, ‘Never, ever again’.

“It is about making sure . . . that we have a message that is relevant to people today, that shows we love this modern country as it is and that shows that we think our best days lie ahead as a country.”

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