David Cameron: I'll pull the plug on Brown

He's miles ahead in the polls, and is set to score handsomely in next month's elections. This time next year, the Conservative leader can expect to be Prime Minister. Except that he knows he can afford to take nothing for granted

'It's a big thing to change your government, to throw out the lot that you've got at the moment,' says Cameron (REUTERS)

David Cameron's bicycle, his prized possession, was stolen from outside his home in west London last Wednesday. The shiny silver and black Scott bike was there shortly after 8am, securely locked to the railings. Minutes later it disappeared. Nicked in an audacious raid, from practically right under his nose.

To the Tory leader and his party, this must be what waiting for power is like.

As it stands, Gordon Brown's Government is reeling from setback after setback. The Prime Minister's authority appears to be draining away. He is openly ridiculed by members of his own Cabinet, his expenses claim left open to question, his Government's policy dictated to a minister by Joanna Lumley, the economy trapped in recession.

To Mr Cameron, the glittering prize of election victory must seem safe, locked in place, despite his protestations of "no room for complacency". This is what all the polls suggest. But the risk is, as Mr Cameron witnessed as a young Tory adviser in 1992 when Labour seemed on course to win, that victory can be snatched away.

The day after the bike theft, I join Mr Cameron for nine hours of campaigning for the 4 June local and European elections.

It is Thursday 7 May, and in exactly a year's time, if the polls are right and if Mr Brown is not ejected from office before then, Mr Cameron could be standing on the steps of 10 Downing Street having overnight brought to an end 13 years of Labour government. I point out the date to the Tory leader as we sit in the back of his car, travelling between picturesque towns in Derbyshire, one of the county councils the Tories hope to win from Labour next month.

Mr Cameron, taking an opportunity to grab lunch between campaign visits, remains expressionless as he eats his BLT sandwich.

But, as it is widely expected that Mr Brown plans a 6 May election, this date must now be etched in his brain; he has probably already thought about the suit, and the words he hopes to use to launch his premiership.

Paraphrasing Boris Johnson, I ask whether he accepts there will be voters, on 6 May 2010, whose pencils will hover over the Conservative name on the ballot paper because they are not yet convinced by his Tory party, by what he offers as prime minister.

"Of course, of course," Mr Cameron says. "You have an enormous task in opposition to convince people. It's a big thing to change your government, to throw out the lot that you've got at the moment. It's a very big thing you're asking." But, he claims, the Tory party is already "demonstrating that we have a strong team, it's a united team, it's got a lot of talent in it, strengthened by the arrival of Ken Clarke".

"There is never one moment when the deal is sealed, the bargain is struck. You've got to convince people all the time that yes, we are the right people to bring the changes you want to see, but also yes, we will be strong, united, dedicated, and work hard, and be responsible, and you've got to go on convincing people of that. I accept there's always more to be done.

"And there really isn't any complacency by my office, me, the top team. We know what a big ask it is to win an election when you start with only 190 or so MPs; it's an enormous ask. But I think we are ready to give that service, and people want it."

His reference to serving sounds a little Blairite, and it is easy to make comparisons between Mr Cameron today and the Tony Blair who appeared effortlessly to charm voters in 1997. In fact, on several occasions, from the moment we board the train at St Pancras to arriving back in London shortly after 8pm, members of the public spontaneously approach him with open warmth, which is reciprocated.

On the homeward journey, he invites a young Indian woman, fighting the closure of her centre against forced marriages, to sit down next to him for a five-minute chat. Later a young man, his arm in a sling, approaches to wish him luck. I start to wonder whether I should demand they prove they are not party workers hired from Central Office. This enthusiasm from strangers must be what it was like for Mr Blair before people turned against him over Iraq.

There is, however, one point during the day when Mr Cameron is greeted with dissent. Leaving a school in Nottinghamshire, his car sweeps past a one-woman protest at the side of the road. Her placard reads: "No state funeral for Margaret Thatcher or Boris Johnson", but he pretends to ignore it.

The Tory leader says he wants to engage with people, one by one, in train seats or marginal seats. If Mr Cameron wins in a year's time, he will find himself in a bubble of security and officials, and this easy contact will be gone.

Mr Cameron sees last year's Crewe and Nantwich by-election as a landmark, when traditional Labour voters, who had never even voted for Margaret Thatcher, switched straight to the Conservatives. But in September, Lehman Brothers collapsed and the economy crashed, and those voters began to drift back to Labour. They are returning once again to the Tories, he believes, but slowly. Their pencils are still hovering.

As part of the day's campaigning, Mr Cameron will attend his 30th "Cameron Direct" – his version of a town hall Q&A – where any voters and any questions are invited. By polling day, he says, he will have visited 100 of the most marginal seats.

Despite this relentless schedule, Mr Cameron, and his wife Samantha, remain grieving parents. After their eldest son Ivan died in February, Mr Cameron took two weeks off work. The Camerons comforted each other as a family, but the Tory leader also found solace by gardening at their home in Oxfordshire. He boasts about the orderly rows of broad beans and parsnips he is growing, but also, scattered haphazardly, are the first shoots of carrots, the work of Nancy, five.

At the Cameron Direct session later, he is asked about special needs provision in schools, and he refers to Ivan. Later that evening, he will join Samantha at a fundraising event for the Special Yoga Centre in north-west London, which helped their son.

On the day that Ivan died, a Wednesday, Mr Brown paid a touching tribute to the six-year-old before Prime Minister's Questions was suspended. When Mr Cameron returned to the Commons cockpit, there seemed to be a new understanding and respect between the two leaders.

Yet, 24 hours before the Derbyshire visit, the Commons chamber rang with Tory jeers as Mr Brown was the subject of relentless and personal attacks by Mr Cameron and his backbench MPs. It was painful to watch. I ask Mr Cameron whether he is concerned of a perception that he comes across as a "public school bully", but the Old Etonian disagrees.

"I profoundly believe this country is facing a completely wasted year under a Prime Minister who, for whatever reason, has lost political authority, moral authority and has also run out of money, and leaves a disastrous economic legacy.

"I have been frustrated that we have got to have this wasted year. If my frustration occasionally surfaces at Prime Minister's Questions, then that's life, that's how I feel.

"I think people expect a robust exchange at Prime Minister's Questions, particularly when the country has been left with this appalling debt hangover by a government that now everyone can see has been absolutely incompetent on an absolutely massive scale. They don't expect us to take teacups and talk about it in a reasonable way. I think the Labour Government has behaved in a very unreasonable way, and I don't apologise for letting my passion about this show."

Mr Cameron laughs at the idea that Mr Brown is a victim of bullying by comparing his press secretary to the No 10 spin doctor who resigned over attempts to smear the Tory leader.

"Look at the people who I employ and the people he employs. Let's have a line-up; let's have a compare and contrast between, you know, Gabby Bertin and Damian McBride."

This is disingenuous, because while Ms Bertin is well liked by journalists, he fails to mention Andy Coulson, his hard-nosed director of communications. Mr Coulson is back at Tory HQ overseeing the Tory response to the Gurkha story. As we speak, chaotic scenes are unfolding at 4 Millbank between Joanna Lumley and the immigration minister, Phil Woolas.

In the market towns of the east Midlands, this farcical turbulence of the Westminster village seems thousands of miles away. But, in the Commons next month, Mr Cameron has the potential to bring down the Government over the part-privatisation of Royal Mail. There could be as many as 120 Labour rebels against the Bill, forcing Mr Brown to rely on Tory votes.

Mr Cameron stops short of giving a cast-iron guarantee that his party will back the Government and rescue the Prime Minister, suggesting that any compromises inserted into the Bill to appease the rebels will lose Tory support. Asked to offer the guarantee, he says: "Yes, as long as the Government doesn't do something crazy and change its mind and do a U-turn. We support part-privatisation of the Post Office... So as long as they don't do something crazy and suddenly change their plans, and as long as they answer reasonable questions about the structures of what they are putting in place, and as long as they are reasonable about how much time the House of Commons has to debate and discuss this."

Mr Cameron says it is not a case of rescuing the Government, but voting for legislation that he thinks is right. "You are not going to bring the Government down over this. You are going to bring the Government down if there's an issue of confidence."

The Tory leader is also determined to push ahead, after the 4 June elections, with his controversial commitment to withdraw from the European People's Party of Nicolas Sarkozy and Angela Merkel and form a new Eurosceptic grouping which will include the Polish PiS party, one of whose members views homosexuality as the "downfall of civilisation".

He insists the Tories want to remain members of the EU and support free trade and co-operation between nation states.

But he adds: "We think Europe needs to change its agenda from being obsessed with institutional reform and endlessly taking further powers unto itself. I think actually forming a group of like-minded parties across Europe that share the elements of this agenda is a sensible thing to do."

President Sarkozy and Chancellor Merkel "understand" his position, Mr Cameron claims, and that the Conservative Party and its new grouping will be "good neighbours rather than unhappy tenants" of the EPP.

I ask whether "like-minded people" includes a party that is anti-gay rights. He says: "Of course, in any group, you may not agree with all your partners about everything. But the key thing is on the issue of the shape and development of the European Union."

The Cameron Direct event is held at Carlton le Willows school, in the Nottinghamshire constituency of Gedling, 91st on the Tory target list with a Labour majority of 3,811.

From the audience of 150, Mr Cameron spends an hour taking questions dominated by the economy but including fossil fuels, education and MPs' expenses. It is a few hours before news breaks that The Daily Telegraph has the detail of every expense claim by every MP, but here it is already a huge issue. Mr Cameron reassures them that "MPs should be scrutinised" and "be held accountable". Later, as the train pulls in to St Pancras, the Telegraph story is emerging. I don't detect any hint that there are Tory scandals about to break, but he is clearly practised in giving little away.

In future, the Tory leader's new bicycle will not be left outside chained to the railings. But with the likely date of the election a year away, there is always the chance that victory could be snatched from him.

Cameron's path to the top

1966 David William Duncan Cameron born in London.

1979-84 Attends Eton.

1985-88 Studies politics, philosophy and economics at Brasenose College, Oxford. Belongs to the notoriously exclusive and hard-partying Bullingdon Club.

1988-92 Works at Conservative Research Department.

1992 Adviser to John Major on election campaign.

1992-93 Special adviser to Chancellor Norman Lamont.

1993-94 Special adviser to Home Secretary Michael Howard.

1994-2001 Works at Carlton Communications.

2001 Elected MP for Witney.

2005 Elected Conservative leader. Refuses to deny dabbling with drugs as a student.

July 2006 Delivers his "hug a hoodie" speech, repositioning party's stance on law and order.

October 2007 Impresses conference with a passionate speech without notes. Subsequent poll rise is a factor in Gordon Brown's opting against a snap election.