Final debate brings the David and David roadshow to an end

Drink and drugs are shaping up as the unlikely twin themes of the Conservative Party leadership race.

Dodgy-sounding cocktails and illegal student substances have already been extensively debated by the Davids Cameron and Davis, but yesterday alcohol provided another flashpoint for the leadership campaigners.

Mr Davis, on the party's traditional wing, complained that binge drinkers upset respectable Conservative voters. He wanted their drinking habits curbed. But in the new-look Conservative Party that David Cameron wants to create, young revellers are seen instead as possible Tory voters.

Extended drinking hours produced the liveliest exchange in the last televised head-to-head debate between the two contestants in this very extended election. Mr Davis was adamant that a Conservative government should reverse the relaxation of licensing laws, while Mr Cameron was clearly alarmed that talk like that would turn away the young voters he is anxious to attract. "We have a situation where the centres of many towns and cities in this country are no-go areas for decent people," Mr Davis said. "We have to recognise that, and recognise that what the Government is doing today is actually making that much worse."

Mr Cameron retorted: "When you say 'no-go areas for decent people' you are almost implying that anyone who does go out is not a decent person.

"You have got to be very, very careful David. That's something the Conservative Party has got to understand. We have to show we understand people's aspirations and not sound all the time as if we are preaching to people."

Mr Davis came back. "That doesn't help somebody who has got somebody vomiting in their front drive. If you go talk to people in many of these towns and cities and ask them, 'Can you go to the centre of Nottingham or Manchester after eight o'clock at night?' they say: 'No, and I want you, the politicians, to sort it out, not to give us platitudes, to sort it out.' "

Mr Cameron insisted that it would give the Conservatives an "image problem" if they sounded as if they could not understand people who go out drinking.

"We mustn't make everyone who wants to go out and have a drink on a Friday or Saturday night sound like a criminal," he said.

"There is a danger sometimes of doing that if we are not careful about the language that we use and the policies we come up with and the way we interact with people."

Another lively moment in the hour-long debate, broadcast last night on Sky TV, came when Amanda Platell, former spin doctor for William Hague, tried in vain to extract more detail from Mr Cameron about rumours that he experimented with class-A drugs before entering politics. He stuck to his line that even a politician is allowed a private past life.

Sky's political editor, Adam Boulton, asked the studio audience whether having taken class-A drugs should automatically bar anyone from being a prime minister. Only two people in the audience voted 'yes', whilst a forest of hands went up to vote 'no'.

The two who took the hard line were a man and woman who had arrived together and were sitting side by side - the man being Chris Kelly, a volunteer helper from the Davis campaign.

Mr Cameron also made a short appearance yesterday on Channel 4's Richard and Judy programme, during which he was given a chance to deny that his background - Eton and Oxford - made him out of touch with the general public.

He implied that every child should have the benefit of a public school education. "I had a wonderful upbringing," he said, "and I went to a fantastic school and I want that for other people."

Earlier, one of Mr Cameron's leading supporters, the Conservative MP Michael Gove, made a suggestion which was unlikely to win Mr Cameron any votes among parents of teenage children, especially those who cannot afford to pay for an expensive education. He said the way to give universities more freedom would be to lift the current £3,000-a-year limit on tuition fees.

Mr Cameron's spokesman said afterwards that this was not his policy, although he supported the principle of charging fees.