Tony Blair liked to roll up his sleeves when he wanted to get the job done. Gordon Brown pulls up his socks. Maybe it is a nervous tick or a throwback from schooldays, but the prime minister has an unconscious need to feel thick black Scottish wool high against his shin.

Tomorrow morning he will give his first address as Labour leader to the party conference in Bournemouth and next week he will celebrate his first 100 days in the job he craved for so long. Yet he still managed to look sheepish on Friday when it was pointed out to him that his socks were hanging around his ankles.

That, so the acolytes say, is the beauty of Gordon. He is natural – unlike Blair. During the leadership campaign, Brown was seen walking about with one trouser leg stuck in his sock. Blair would not have been caught out like that. His successor is clumsy and austere maybe, but natural.

On Friday afternoon he looked glum and baggy-eyed. To be fair, he had just been to a friend’s funeral. But you would think that the prime minister would be chipper, given that he has enjoyed consistent poll leads since he took office nearly three months ago.

Yes, there has been the credit crunch crisis, the summer floods and foot and mouth, but David Cameron is definitely on the ropes. The Tory leader’s senior lieutenants looked mightily depressed last week as the opinion polls showed that the Brown “bounce” was still bouncing.

Yet only rarely did Big Gordie break into a smile during our interview, despite the good news. Maybe it is all those years of being the No 2 in government. (He livened up at the mention of the departure of Jose Mourinho, the Chelsea manager, and his replacement by a backroom boy Avram Grant.) But more likely it is because Brown has a massive dilemma on his hands: should he call a snap election or not?

He is clearly uncertain, troubled by the temptation, and would not be drawn on the subject. “My focus is, and will remain, on the work that needs to be done,” he said. “The return of parliament, the Queen’s speech and the economy.” No clues on the election date, then? “I think that getting on with the job is what I’m doing, focusing on the work in hand.”

The prime minister would not be swayed. Any word out of line, he knows, will make a big story. He has been in power for three months, handled unexpected events well, but critics have said that although he has proved adept at the “vision thing”, he lacks substance in his new role, something that he could never have been accused of as a decidedly hands-on chancellor.

Sitting in the “Thatcher Study”, on the first floor of No 10, overlooking the rose garden where the Blair family’s garden furniture has been replaced with a plastic playhouse for the Brown children, he revealed that his big theme for the party conference is the health service.

As chancellor he oversaw the influx of funds into the NHS and attempts at reform, but according to a report this month by Sir Derek Wanless, whose analysis had inspired the flood of cash, it has made little difference. “The important thing about the health service is people rightly want a higher standard,” Brown acknowledged.

“And people want a personal service, they want personal care, [their] needs taken seriously. So they want to be able to see a doctor in a hospital at the times that they want. And they want to meet the doctor and consultant that they choose and they want to do things with a quality that is far higher than before.”

It seems that Brown’s “big idea” is simply to “intensify” – a word he used often during our interview – the reforms that Blair had already put in place, rather than find a new direction. He talked passionately about “tailoring” public services for individual customers – a laudable goal for any prime minister.

It might not sound that ambitious, but Brown’s big announcements this week will be about achievable goals. They will be about, his aides say, issues that matter to ordinary people: speedier screening for cervical and bowel cancer and fast-tracking patients for other screening programmes. Such an approach is typical Brown: practical, realistic, not promising the world.

“We must go further to reduce waiting times for cancer treatment and expand cancer screening,” he said. “That means millions more people routinely screened for cancer, and where there is cancer suspected, earlier treatment and a better chance of survival.”

The prime minister also posited a new way of dealing with a key issue that fills hospital patients with dread: MRSA, the so-called superbug. He and his advisers have looked to America for radical solutions and he will announce that “deep cleaning” of wards will take place at least once a year.

On this subject Brown hit his stride. It seems as if, like Blair, while determined to rein in inflation-busting pay rises in the public services, he is set on customer-led reforms.

“People will see that the reform agenda is moving forward, but we are a nation of rising aspirations that have got to be met by better opportunities for children and young people,” he said.

“Rising standards of service in public services that are not just available to all but tailored to people’s needs. And running through what I’ve listened to and learnt, as I’ve gone around the country and heard the need for change, is that people want their rising aspirations met by new opportunities in education, employment and work-life balance and the opportunity to buy their own homes, the opportunity to get higher-quality housing.

“And at the same time, of course, people also want a rising standard of public sector services and whether it’s policing on the beat and it’s hospital services that are there when you need them, or whether it’s education where your child gets personal attention, individual attention, then the reform agenda is about universal public services that are accessible to all, but they’re actually personal to each of us.”

In recent weeks the public has been worried about the effects of the credit crunch crisis that has engulfed Northern Rock and threatens higher mortgage payments. Brown has been criticised for allowing the credit boom to progress unhindered and for splitting the regulation of the financial markets between Treasury, Bank of England and the Financial Services Authority while he was chancellor, meaning there was no clear hand on the tiller when the crisis broke.

Brown would not be drawn into criticism of the governor of the Bank of England and countered that the problem was global. “We were looking at events that started off in America, were happening in Germany and which are impacting on every industrial economy, and where every economy, including that of Britain, is bound to be affected from issues that started in the mortgage market in America,” he said.

“And I think it’s our strength as an economy that has enabled us to be able to help the depositors in Northern Rock in a way that we’ve been able to guarantee.”

As witnesses in his defence, Brown referred to the economy’s ability to cope with the crises that hit Russia and Asia in the late 1990s. His line is: the British economy is stable, it is sound and can withstand such problems.

“You know at each point when we’ve had to deal with the problems, and face these challenges, the British economy has proved itself strong and stable and capable of withstanding difficult international events as they arise. We will always be vigilant and never be complacent. And I think that you will have seen that in the way that Alistair Darling has dealt with the events of the past few days.”

Was he worried that the crisis might derail his election plans? Maybe privately; but the prime minister does not give anything away. “Vigilance is obviously essential and I think that people have seen in the past few days how, by taking decisive action, we’ve been able to deal with the particular issues that arose from Northern Rock. But equally there was more liquidity available in the economy as a result of decisions that have been made.”

Turning to immigration, Brown can afford to be stern but fair. While the Tories get accused of “lurching to the right”, Labour can be as hard as it likes – a message he acknowledged. Brown has been keen to emphasise that British jobs should be for British people. He does not say – as Cameron has – that the number of migrants entering the country is too great, but instead offered a measured approach.

“I obviously recognise the contribution that people who have come to our country have made to our economy,” he said.

“I think people do recognise that. It’s a policy in our country of managed migration. We’re stepping up controls by introducing a points system. I am very clear that people have responsibilities as potential incomers to our country to learn our language, to understand our traditions, to meet their obligations, to play by the rules in this country.

“I think you will see that citizenship and also presence in our country have to be met by people who accept their duties and obligations to the country to which they have come.”

Sitting in Margaret Thatcher’s former room, he makes it clear that he enjoyed meeting her in Downing Street recently. “We discussed how the room had changed and how she worked here,” he said.

These days Brown tends to use it as his own quiet study, with a laptop computer and an in-tray – containing letters drafted for him to the bereaved families of soldiers lost in Afghanistan and Iraq.

The letters are a reminder of the ground upon which Blair floundered. Where does Brown believe that Britain’s priorities lie – Iraq or Afghanistan?

“They are both very important,” he said. “The safety and security of our military personnel, who are bravely and with great heroism serving our country, and our duty to protect and make them secure in difficult circumstances are a priority.” Does he imagine that UK troops will still be in the Basra region in a year’s time? Again, he does not commit himself. “We will continue to discharge our responsibilities in Iraq. We are, like America, trying to move the situation from one where we are responsible for the security of these provinces to a situation where in Basra the Iraqi army and the Iraqi police themselves are responsible for the security.”

While Thatcher’s room is for reflection, most of the time Brown uses the downstairs “den” off the cabinet room, the favoured meeting place of Blair. It is not called the den any more, of course. It is now “Gordon’s room”.

It was here on Friday that he was putting the finishing touches to his conference speech with his inner circle: Ed Balls, the schools secretary, Bob Shrum, the American poll-ster, Douglas Alexander, the election co-ordinator, and Ed Miliband, the manifesto writer.

Brown typed on his computer and ran through the draft of the speech, his words appearing on a screen on the wall for analysis and revision. Blair barely used a computer and shunned electronic media, but Brown loves innovation: he was an early addict of mobile phones and e-mail and his aides find it hard to keep him away from his laptop.

As chancellor he controlled the domestic policy agenda – normally a prime minister’s preserve. When asked about the difference now between the two jobs, he flashes a smile for the first time during our interview. “When you’re chancellor you’re dealing with economic issues. When you’re in the job that I’m in now you have to recognise there is a far wider range of challenges you’ve got to meet.” No, really Gordon?

A happy and satisfied man at last, he is clearly relieved that the public apparently perceives him as a safe pair of hands in a crisis, if the polls are right.

“You would not have expected that this summer, in only a few weeks, we would have had to deal with a very big terrorist threat . . . and then the worst floods for 150 years . . . and then, of course, people were very surprised by the incidence of foot and mouth . . . and obviously the issues on the financial markets. So there have been a range of things that are a challenge to deal with.”

Old habits die hard. Brown is a voracious reader, able to devour any book in a matter of hours, and there is evidence of his addiction in No 10. Amid the drafts of his conference speech is a manuscript he is compiling, Courage in War-time. On the table next to his desk are Churchill’s Promised Land, Thatcher’s Statecraft and a collection of Nelson Man-dela’s speeches: hard going for most, staple matter for Gordon. It will all go into the big speech to conference tomorrow.

A clock chimes loudly. Time to make up his mind. Will his speech include an election annoucement, or not?

The key issues facing the parties
Roland White

Education
By rights, Labour should be tucking a large book down the back of its trousers and preparing for a diffi cult interview with the headmaster. Remember “education, education, education”? Well, half of our 15-year-olds still fail to get fi ve GCSEs at A-C grade. Luckily for Gordon Brown, David Cameron failed his political 11-plus this summer by highlighting a party split over grammar schools.

Immigration
The most explosive election issue of them all, but more of a threat to Cameron than Brown. When the Tories talk about immigration, the voters think they’re racist. Labour would have to talk about “rivers of blood” to attract the same sort of criticism.

The economy
During the biggest economic crisis to hit this country since Black Wednesday, the prime minister slipped into his disguise as Macavity the Mystery Cat and was suddenly nowhere to be seen. Was he queueing to get his savings from the nearest Northern Rock? If the economy isn’t as strong as advertised, Cameron could fi nd himself leading in the polls again.

Law and order
We now live in a society in which an 11-year-old boy can be shot dead while cycling home from football practice. But yet again the voters appear to have put this down to a long-term decline and the government has escaped unscathed.

Health
A report has just criticised Labour for failing to use £50bn extra health spending as wisely as he had hoped. But the NHS is so large and unwieldy that the public doesn’t seem to think anyone else has any better medicine

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