Leading article: Barack Obama is America's future

The Republicans have made a last-minute attempt to prevent Barack Obama’s ascent to the White House by trying to recruit an Oxford academic to “prove” that his autobiography was ghostwritten by a former terrorist.

With two days before the election, Obama is poised to become America’s first black president, according to polls showing he has an average six-point lead over John McCain, his Republican opponent.

Dr Peter Millican, a philosophy don at Hertford College, Oxford, has devised a computer software program that can detect when works are by the same author by comparing favourite words and phrases.

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He was contacted last weekend and offered $10,000 (£6,200) to assess alleged similarities between Obama’s bestseller, Dreams from My Father, and Fugitive Days, a memoir by William Ayers.

Ayers, now a university professor in Chicago, co-founded the Weathermen, a radical 1960s underground group that bombed government buildings in Washington and New York. The Republicans accuse Obama of “palling around” with him.

The offer to Millican to prove that Ayers wrote Obama’s book was made by Robert Fox, a California businessman and brother-in-law of Chris Cannon, a Republican congressman from Utah. He hoped to corroborate a theory advanced by Jack Cashill, an American writer.

Fox and Cannon each suggested to The Sunday Times that the other had taken the initiative.

Cannon said that he merely recommended computer testing of the books. He doubted whether Obama wrote his autobiography, adding: “If Ayers was the author, that would be interesting.”

Fox said he had hoped that Cannon would raise the $10,000 to run a computer test. “It was Congressman Cannon who initially pointed me in that direction and, from our conversation, I thought he might be able to find someone [to raise the $10,000].”

He believed that if “proof” of Ayers’s involvement was provided by an Oxford academic it would be political dynamite.

Fox contacted Millican, who said: “He was entirely upfront about this. He offered me $10,000 and sent me electronic versions of the text from both books.”

Millican took a preliminary look and found the charges “very implausible”. A deal was agreed for more detailed research but when Millican said the results had to be made public, even if no link to Ayers was proved, interest waned.

Millican said: “I thought it was extremely unlikely that we would get a positive result. It is the sort of thing where people make claims after seeing a few crude similarities and go overboard on them.” He said Fox gave him the impression that Cannon had got “cold feet about it being seen to be funded by the Republicans”.

Cannon insisted, however, that he was not interested in making an issue of Obama’s memoir “even if it were scientifically proven” to be someone else’s work.

Obama said this weekend that the campaign would “get nasty” in its closing days. Last night he was forced to deny that he knew a Kenyan aunt was living illegally in the US. Zeituni Onyango, half sister of his late father, lost a bid for asylum in 2004. Obama said he had no knowledge of her status, but that the law should be obeyed.

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