IAIN DUNCAN SMITH was under renewed pressure last night as Tory MPs unhappy with his leadership said that they had enough support to trigger a ballot to depose him.

Senior Conservatives were asserting that discontent had reached such a pitch that it would be little problem to collect the 25 signatures to force a leadership vote.

Yet they admitted that there was no sign of anyone seeking to trigger an election. There is no consensus about a possible successor and many MPs believe that to drop him so soon after last year’s leadership contest would add to the public view that the Tories are unfit for government. Even so, the disclosure of such misgivings among MPs is a huge blow to Mr Duncan Smith likely to be capitalised upon by Labour in the Commons today.

The fresh signs of discontent coincided with a MORI Political Monitor poll which found that 39 per cent of Tory supporters were not satisfied with his leadership, compared with 32 per cent who were. More ominously, 38 per cent of the public had no view on his performance as leader.

Rules introduced after William Hague’s election as Tory leader in 1997 require 15 per cent of the parliamentary party to request a leadership election in which MPs choose two names to put to a ballot of all members of the party.

The Tory Left is most distrustful of Mr Duncan Smith, believing his strategy of “parking” Europe and campaigning on public services lacks credibility given his record as a Maastricht rebel.

There is no obvious alternative. The most likely candidate is seen as David Davis, whose constituency is on the Thatcherite Right. Kenneth Clarke remains a substantial figure, but has stood unsuccessfully twice. Theresa May’s stature has increased after her conference speech.

Even close supporters of Mr Duncan Smith were despondent after he said a fortnight ago that no one knew whether A levels were “worth the paper they were written on”. But it was his mishandled sacking of Mr Davis as party chairman in July that unleashed the gloom.

Traditionally a Tory leader who lost his MPs’ confidence could expect a visit from the executive of the 1922 Committee of backbenchers, to tell him to go, but some say the body no longer carries the weight it did.

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