"Prudence is the other woman in Gordon's life," a Brown aide once said.

Gordon Brown is a workaholic

But the Tories have been quick to blame "Culpability Brown", as his opposite Francis Maude called him during their annual conference, for squandering their "golden economic legacy".

And Mr Brown's boast he had "brought an end to boom and bust" could return to haunt him in future months.

Power has created a new energy within Mr Brown - a politician well known for his gruelling work schedule.

Presbyterian background

There have been many attempts to correlate Mr Brown's vision of society with his father's Presbyterian preaching.

Brown's political career began when most children are still deciding which football team to support let alone which party.

At 12, he was canvassing for Labour and by his 20s he was a leading political activist in Scotland, cutting his teeth helping Robin Cook, now the foreign secretary.

Mr Brown went to Kirkcaldy High School, entering Edinburgh University at 16 and becoming rector at 21.

His early career was spent lecturing, working in television and making a name for himself in the Scottish Labour party.

John Smith's death in 1994 devastated Brown

His first attempt to enter Westminster, for Edinburgh South in 1979, won thwarted by the present Tory party chairman Michael Ancram.

An occasionally strained partnership

In 1983, he took Dunfermline East, a new constituency including Rosyth naval base, pit villages and coastal towns.

Entering Westminster with the 1983 intake, he came to share an office with the newly elected MP for Sedgefield, Tony Blair.

Mr Brown educated Mr Blair in writing press releases, manipulating the media and structuring his speeches.

The pair came into government already knowing each other better than most politicians get to know each other through their whole career.

Paul Routledge's authorised biography of the chancellor describes how the partnership changed when leader John Smith's suddenly died in 1994.

A two year silence existed between Brown and Mandelson

The book claims Mr Brown is convinced he could have beaten Mr Blair in the leadership contest, but the prime minister broke a secret pact between them.

For nearly two years Mr Brown was morose and gained weight, but in the run up to the election he worked himself out of his personal trough to emerge fitter, leaner and tougher.

"You can't trust the Tories," became his and the party's repeated battle cry against the Conservatives.

During the campaign, Mr Brown came up with the idea that an anti-sleaze candidate should stand against disgraced Tory minister Neil Hamilton.

Honeymoon promises

The chancellor immediately acted to free up the Bank of England

Within weeks, Mr Brown was entering 11 Downing Street and "hitting the ground running".

The new chancellor immediately went about transferring control of interest rates to the Bank of England.

He quickly brought in Labour's first budget in a generation to implement his welfare-to work programme, paid for by imposing the windfall tax on privatised utilities, and to fulfil manifesto pledges to lift VAT on fuel.

Earlier this year, Mr Brown announced the results of the Treasury's year-long Comprehensive Spending Review.

In a speech which resulted in "Spend, Spend, Spend" headlines, the chancellor told the Commons cash for health over the next three years would rise by £21bn, and an extra £19bn was to be spent on education.

The exercise was driven by the Treasury, which, having relinquished control over interest-rate policy, was anxious to extend its tentacles into the spending decisions of each ministry.

More recently, he has met with calls for a cut in interest rates to protect jobs dependent on the exports following the continued strength of the pound.

Sacks of Valentine cards

The last 18 months has also seen a softening of Mr Brown's dour image.

The chancellor is a housewife's favourite, receiving sacks of Valentine cards.

Mr Brown has had a series of discreet relationships with glamorous career women which have ended mainly because of his commitment to politics.

Although his current relationship with PR consultant Sarah Macaulay had been known for some time, the first evidence of the couple was a photograph taken of them dining at an Italian restaurant in Soho last year.

Since Mr Brown has been seeing Miss Macaulay, the chancellor has undergone a physical transformation. He lost a stone-and-a-half through daily sessions on the treadmill at his Westminster gym and he appears more relaxed.

Gordon Brown appears more relaxed with Sarah Macaulay

"I don't think people are terribly interested in my private life," he once said.

Outside interests: politics

But the chancellor regards almost everything else outside politics as a waste of time.

He is reported as saying: "I don't like formal dinners or social activities in general."

His private "waste of time" list includes parliament but recently, Mr Brown declared there was more to life than trying to manoeuvre Tony Blair out of No 10.

During his speech at this year's Blackpool conference, he stated: "These goals are what I know. I am here to play a part in achieving them.