His declaration at his campaign launch that "we have just wasted four years before suffering the most humiliating defeat in Conservative history" is typical of his combative, take-me-as-I-am style.

In the current spin doctored era, the Hush Puppy-wearing, jazz-loving beer drinker who could do with going on a diet enjoys a wide appeal. Several opinion polls have suggested the ex-chancellor to be the most popular choice for Tory leader among voters, and the party rank and file backed him when William Hague beat him to the succession in 1997.

Clarke boasts the greatest ministerial experience of the field: he served in government for the full 18 years of Tory reign from 1979 to 1997, health, education and home secretary among his jobs.

He is unrepentantly on the pro-European, One Nation wing of the Tory Party and spent the last four years on the backbenches making little secret of his disagreement with the leadership. He is by no means above pragmatism, though, as shown by the startling pact between himself and the super-sceptic John Redwood for the final round of the 1997 contest.

This time round, Clarke hopes to resolve the apparently unbridgeable Tory gulf over the euro by allowing "a free vote and freedom in debate" on the single currency.

It has proved enough to have won over the Eurosceptic Henley MP Boris Johnson to his side, and has helped him oust the early leadership frontrunner Michael Portillo from his top spot.