Oh I do like to be beside the seaside

A concerted attempt by senior Tories to bolster Iain Duncan Smith's ailing leadership was undermined last night when growing concern about his performance emerged in public criticism by MPs and grassroots activists.

Two former cabinet ministers on the Tory left, Kenneth Clarke and Stephen Dorrell, added to the pressure on Mr Duncan Smith by making critical speeches at fringe meetings at the Tory conference in Blackpool. Some chairmen of local Tory associations are expected to question his leadership at a private meeting today.

Most of the recent sniping at Mr Duncan Smith has been made in off-the-record remarks. But some critics went public yesterday, despite pleas for loyalty and unity by members of the Shadow Cabinet who launched a fightback on the opening day of the conference.

In an attempt to regain the political initiative, shadow home secretary Oliver Letwin will today announce plans to put police forces under the control of elected sheriffs or mayors.

Mr Clarke, a former Chancellor, told The Independent's fringe meeting in Blackpool that he did not know what the Tories' policies were.

He criticised Mr Duncan Smith's move to put tax cuts at the heart of the party's agenda, saying it should safeguard public services first. Mr Clarke rebuffed an appeal by David Davis, the shadow Deputy Prime Minister, for him to rally behind the leadership by joining the Shadow Cabinet.

Mr Dorrell, a former health secretary, told another fringe meeting that the Tories' third place in last month's Brent East by-election showed that voters did not regard the Conservative Party as a viable vehicle for their protest. He said: "However disenchanted with the Government they become, voters do not look to the Conservatives to provide them with the means of 'getting the scoundrels out'."

Writing in The Independent today, Sir Christopher Gent, the former Vodaphone chief executive who now heads the Reform think tank, warns that the Tories are confused over policy. "The Conservative Party seems uncertain whether to embrace reform or to regress, and in turn voters are uncertain what the party stands for," he says.

Jonathan Steele, chairman of the Buckinghamshire constituency of Beaconsfield, said: "We will support our leader, whoever it is. If Mr Duncan Smith performs well, then it will be him. However, if he does not, we have the right to reconsider our position."

Felix Aubel, prospective Tory candidate for Brecon and Radnorshire, said: "To be a prospective prime minister you have to have charisma, you have to attack the Government very hard and I am very sorry to say that Iain Duncan Smith has not been as successful as he should have been. People do not elect a quiet man, in quotation marks, as prime minister."

John Bercow, who resigned from the Shadow Cabinet over the party's direction under Mr Duncan Smith, said last night: "We must spend more time thinking about what is wanted by people who do not vote Conservative rather than by what is wanted by those who do. Our challenge is to make an effective pitch to the centre ground of the political landscape."

Theresa May, the Tory chairman, opened the conference with a plea for the party to rally behind its leader. But she said: "One question still hangs in the air. Labour has done enough to lose the next election. Have we done enough to win?"

Tim Collins, the shadow Transport Secretary, urged the Tory leader's critics to "relearn the virtues of loyalty". He told the conference: "Let the message go forth to every Conservative, however eminent, senior or self-important: if you can't say anything positive about your party, kindly don't say anything at all."

Despite the attempt to rally round the beleaguered Mr Duncan Smith, there was gloom among senior Tories that a drive to set out the party's policies had been overshadowed by the leadership issue. One frontbencher said: "We have got the worst of all worlds. Iain is suffering death by a thousand cuts. He is limping on. We can't go on like this. We should either back him or get rid of him ­ and quickly."

Michael Ancram, the Tories' deputy leader, became the first senior figure to admit there were "plots" against Mr Duncan Smith, but insisted: "Politics is about plots, but there isn't going to be a successful plot."

Yesterday, Mr Duncan Smith insisted he would lead the Tories to victory at the next general election. But he conceded that people did not yet know enough about his party's programme. "Most of the public say they are ready to listen. They want to know what the alternative is [to Labour] and, to be fair, they don't know."

The Tory leader dismissed the poor opinion polls that marked the start of the conference, as "quite meaningless" and also dismissed speculation about his leadership as "garbage".