Frontrunner Duncan Smith wins backing from Ancram

Michael Ancram, the former Conservative Party chairman, has thrown his weight behind Iain Duncan Smith ahead of tonight's crucial leadership election vote by Tory MPs.

His decision was a big setback for Kenneth Clarke, the former chancellor, who had hoped for Mr Ancram's support. It could also throw a lifeline to Michael Portillo, who is now embroiled in a race for second place with Mr Clarke.

The candidates who finish first and second tonight go forward into the decisive ballot of 300,000 party members, with the result to be declared on 12 September. Tonight's vote is so close that Sir Michael Spicer, chairman of the 1922 Committee, which oversees the contest, met the three candidates yesterday to discuss what would happen in the event of a tie for second place.

Speaking to journalists, Mr Clarke hinted that, if there was a tie, all three names might go into the members' ballot. "There is clearly a case for that view," he said.

Mr Ancram's declaration could sway the votes of a handful of MPs who backed him in last week's first round, when he was eliminated.

There was gloom in the Clarke camp, with aides describing it as "very peculiar" for Mr Ancram, who stood as the unity candidate, to endorse Mr Duncan Smith, a hardline Eurosceptic. "There is no way Duncan Smith can unite the party," said one leading Clarke supporter.

The endorsement is a huge boost for Mr Duncan Smith, who has already won the backing of David Davis, the fifth candidate in the election, and is now expected to top the poll. Mr Ancram is a popular figure among the Tory grassroots and his endorsement is bound to help Mr Duncan Smith win over members worried about his relative inexperience.

Mr Ancram said: "I believe him to be the candidate who can best unite our party, who can best reassert our core Conservative principles and who is best likely to deliver the changes which can create the springboard to victory at the next election."

Offering to play an active role in the Duncan Smith campaign, Mr Ancram said: "I could not support a 'no change' candidate, but at the same time change should not be so radical as to risk undermining the unity of the party, both in parliament and the country at large."

Although Mr Duncan Smith's supporters were jubilant, he insisted: "This is a very tight race. There is no clear leader. Anybody can win." Allies of Mr Duncan Smith now believe he is likely to face Mr Portillo rather than Mr Clarke in the run-off. "This takes the pressure off Portillo," one senior Tory said.

Mr Portillo, who had moved from early front-runner to outsider after a trouble-hit campaign, received another late boost when the outgoing Tory leader, William Hague, distanced himself from the video diary made by Amanda Platell, his former spin-doctor, who accused Mr Portillo's aides of disloyalty. Mr Hague said: "During the election campaign I am confident I had the full support and loyalty of all members of the Shadow Cabinet."