Dark horse Fox is flying the flag as he woos the right wing

A decade later, he won enthusiastic applause from this month's Conservative Party faithful in Blackpool by wrapping himself in the flag, supporting those schools which choose to fly it against "politically correct" criticism.

It was a pitch to become the standard-bearer of the Tory right, which has met with increasing success as the leadership campaign reaches its climax.

The comprehensive schoolboy from East Kilbride has impressed rank and file representatives with his combination of Eurosceptic right-wing credentials and passion for unfashionable social issues such as mental health and domestic violence. In Blackpool he was joined on the platform by his fiancee Jesme Baird, 37, an NHS cancer specialist.

Dr Fox's style has been deliberately modest. While supporters of his opponents were running slick PR campaigns with daily bulletins from the Cameron camp and bottled water and monogrammed fleece jackets from Ken Clarke, Dr Fox's followers could only offer a small business card.

However, behind the scenes, the former Beaconsfield GP has run a stealthy campaign, picking up significant support from the right of the party and among centrists.

Dr Fox, a self-proclaimed Thatcherite, has set himself up as the most right wing of the contenders for the Tory crown. He has threatened to pull Britain out of Europe, and very publicly backed the decision to invade Iraq. He remains close to Margaret Thatcher, and was one of only two leadership contenders to be invited to her 80th birthday party last week.

It has been a campaign in sharp contrast with the modernising message of the Cameron camp. But Dr Fox has steadily picked up support among MPs - much of it behind the scenes - and is regarded as a tough man to beat in a ballot of the membership if he makes it to the final two.

Labour figures look at the prospect of a Fox-led Tory party with some glee. "Write that Fox is the one we are really worried about. He's the one we really fear," said one cabinet minister with a mischievous tone.

Backers of the shadow Foreign Secretary point to a man, who at 44, is from an enthusiastic new generation but has experience of policy and dogfights with Labour. He was born in Lanarkshire, the son of a teacher. Many members of his family were left leaning.

He had a much-mentioned friendship with the singer Natalie Imbruglia, absails down tall buildings for charity and has walked the wings of a bi-plane.

Friends insist the dark horse of the leadership race will make it to the final two today. One said: "He is a very bright guy. He has very sharp opinions."