An Easter visit to a chocolate-maker must have seemed like a good idea for Nicolas Sarkozy, as he strives to show that he’s a warm-hearted guy and no longer just France’s top cop, a fortnight before the presidential vote.

With afternoon sun on his shopfront Sebastien Bouillet, one of the best chocolatiers in Lyons, waited for the arrival of the conservative favourite and recent Interior Minister. Also waiting were Gérard, the town crier and radical militant, a dozen demonstrators and a clutch of young Arabs in hoods.

“Clear out, Sarko. . . you’re fouling our neighbourhood,” boomed Gérard, amid jeering. “It doesn’t look good,” a police officer told the Sarkozy team, and his Citroën turned back down the hill. Riot police stood down while Mr Sarkozy’s team invented a fable about the late arrival of his aircraft.

Mr Sarkozy’s retreat on Thursday from Croix Rousse, a gentrified working-class quarter, exposed the tension of a campaign that has swung into territory usually favoured by Jean-Marie Le Pen and his far-right National Front.

“Why does this always happen to me?” Mr Sarkozy, 52, mused as he was welcomed 30 minutes later at a carpet factory. The candidate, 5ft 6in (1.5m) tall and punchy like James Cagney, flashed the menacing smile that he is struggling to replace with a statesman’s calm. The answer to his question is simple. With his gunslinger’s talk and tough-love plans for France, Sarko is loathed and demonised by left-wing idealists and the young of the ethnic estates. In the campaign, Mr Sarkozy has not set foot in la banlieue, the immigrant districts around the big cities where youths rioted in the autumn of 2005.

For the moment, this does not matter to the leader of the Union for a Popular Movement (UMP) as he keeps his steady lead in a four-way race with Ségolène Royal, 53, the Socialist, Mr Le Pen, 78, and François Bayrou, 56, the centrist.

Mr Sarkozy, who stepped down as Interior Minister last week, is riding the anger of a France in despair over economic stagnation, globalisation, crime and immigration. These were the ingredients for Mr Le Pen’s progress to the run-off in the last election, and they are stronger than ever.

In the final straight to the first-round vote on April 22, Mr Sarkozy has invaded the authoritarian turf of Mr Le Pen, pulling Ms Royal rightwards behind him and isolating Mr Bayrou. The candidate, who plays up his own origin as a “little Frenchman of mixed blood”, is convinced that victory will come from the Right and not the soggy middle ground of Mr Bayrou or the schoolmistressy left-wing ideas of Ms Royal.

Proof, in his eyes, came from an eight-hour battle between police and banlieue youths in the Paris Gare du Nord two weeks ago. It fuelled his law-and-order stance and enabled him to pounce — unfairly — on Ms Royal for siding with rioters.

Unlike Jacques Chirac, the departing French President, “Sarko” dislikes campaigning and pressing the flesh. But he was on form as he laid out his hardened-up line before 20,000 fans in Lyons on Thursday night. He was boosted by his arrival hand-in-hand with Bernadette Chirac, the popular premiãre dame. She was with him for the first time to show that her husband had put their feuds aside and backed his mutinous subordinate. “I will do everything I can to help him,” said Mrs Chirac.

Mr Sarkozy employs Henri Guiano, the speech-writer who helped Mr Chirac to win in 1995, but his muscular rhetoric is more Le Pen than the President’s caring Gaullism. His speech repeated his promises to cut the taxes and red tape that stifle enterprise and employment. “The big problem with France is that it works less while the others work more,” he said. But gone was Sarko the free-marketeer and pro-American.

Instead came Sarko the anti-European protectionist who celebrates “the Gaullish tribes” and is promising a Ministry of National Identity. The EU had betrayed France, he said. Its free-market doctrines were a disaster. France must stop hating itself and rid itself of the guilt complex that has been imposed by the Sixties generation. Only fools argued that immigration did not influence the nation. Immigrants must respect French values. “There is no room in France for polygamy, for female circumcision, for forced marriage, for the Muslim headscarf in schools,” he said.

Mr Sarkozy is leavening this tough talk with an attempt to shed his image as excitable and power-mad. In a book-length manifesto this week, he tells voters: “The young man that I was, in love with adventure and ready to sacrifice all for his ambition, has calmed down as an adult.”

Before the final round on May 6 Mr Sarkozy will broaden and soften his appeal under a new slogan: “Ensemble.” But the race is still open and he is courting a risk by further polarising opinion in an election that is ultimately a referendum on Nicolas Sarkozy.

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