The right-wing candidate for the leadership of Britain's opposition Conservative Party has made a pitch for the votes of moderate party members in the increasingly bitter battle.
Iain Duncan Smith, a eurosceptic backed by former British prime minister Margaret Thatcher, seemed keen to distance himself from perceptions that he was a member of the Conservative old guard seen by many as racist, homophobic and out of touch with the concerns of ordinary Britons.
He told the Sunday Telegraph newspaper that he favours a referendum on Britain's entry to the single European currency and said he would review laws that outlawed cannabis and the promotion of homosexuality.
I think we ought to give the people a referendum, whatever, he said. That was the mistake of our last policy - ruling it out without giving the people a say.
Even though they didn't want to enter the currency they'd rather make the decision themselves. Polls have shown that a majority of Britons would choose to keep the pound.
The result of a postal ballot of about 300,0000 Conservative activists will be announced on September 12.
A former army officer, Duncan Smith also said he would look again at the issue of legalising cannabis and the controversial Clause 28 law which prevents local authorities from promoting homosexuality.
Though Duncan Smith has been ahead in polls of Tory voters, Clarke, who is seen as more popular with the wider public, said a Duncan Smith victory would sink the Tories' chances of leading Britain.
Clarke told the Observer newspaper that the Conservative were moving so far to the right they are beginning to attract the lunatic fringe.