France's students are in revolt. Its urban ghettos are sporadically aflame. Its trades unions are planning national strikes tomorrow. Its discredited 73-year-old president, Jacques Chirac, is serving out his time. An opinion poll, published by Le Figaro newspaper on Saturday, showed that 50 per cent of French people did not have faith in the market economy - compared with 20 per cent in communist China. One of history's eternal questions resounds around Paris once again: can France reform itself without revolution?

On Saturday, in front of his fired-up supporters, Nicolas Sarkozy, the president of the ruling centre-right UMP party, provided his own rhetorical answer to that question. The presidential election of 2007, for which he is a leading contender, would unleash France's creative energies, he said, invoking his latest campaign theme: "Imagine France Afterwards".

In his speech, Mr Sarkozy said that in his 25-year political career he had never seen France more tense and tormented that it was today. "After 20 years of mass unemployment, 15 years of mediocre economic growth, 10 years of weak purchasing power and seven changes of government since 1981, France has lost its illusions," he said. "How can we blame the young for shouting at the top of their voices what their parents think themselves?"

Mr Sarkozy stressed that reforms could only succeed if they were socially fair and thoroughly explained. "The French do not refuse change but they do reject reforms that they think are unjust," he said. "The UMP must consider the spirit of justice as fundamental a principle as the recognition of work, merit and effort."

Mr Sarkozy's speech was a remarkable attempt to distance himself from the government of which he is the second most senior member. It was clearly a swipe at Dominique de Villepin, the prime minister and rival presidential contender, who has provoked a confrontation with students by loosening the labour law. The first job contract (CPE), which Mr de Villepin rammed through parliament without prior consultation with unions, gives employers the right to sack young workers within a two-year trial without having to provide a reason.

The leaders of the opposition Socialist party have condemned the CPE and Mr de Villepin's methods. But they too argue that change is possible if conducted in the right way: the republic's egalitarian traditions will never allow a divisive That­ch­erite approach to reforms.

Jean-Marc Ayrault, the leader of the parliamentary Socialist party, attributes France's troubles to a "democratic blockage" caused by the end of a political reign and a political cycle. "Jacques Chirac no longer has any influence, except to try to stop the rise of Sarkozy and to help de Villepin," he says in an interview. "But we are also reaching the end of a cycle, with a hyper-centralised system that puts all the power in the hands of the president and prime minister."

Mr Ayrault says France needs to adopt a more flexible political system, redefining the state's role and decentralising more power. He argues that the emergence of Ségolène Royal as the Socialist party's most popular figure highlights the voters' desire for change. A rare woman at the top of French politics, Ms Royal incarnates reassurance, moral authority and firmness, he says.

France needs a leader who can articulate a new vision much in the way that Tony Blair did in the UK, he says. "Tony Blair, even if some of his policies would be unacceptable in France, spoke to the British about their country, its future, power, pride. You must know how to tell the story of a country," he says. "Villepin tried but with a backward-looking grandiloquence, talking of a nostalgic vision of France from another epoch."

A recent study of voters' attitudes, The State of Opinion, shows the French deeply ambivalent on whether they want their next president to be a reassuring international statesman or a champion of domestic change.

Brice Teinturier, a pollster at TNS-Sofres, says that over the next year French voters will not only decide who they want to lead them but how they want to be led. "If the situation keeps getting worse then a model of leadership based on action . . . would appear coherent and seductive," he says.

A new president, with a clear mandate for change, would at least be in a stronger position to attempt reform. "Mr de Villepin is the loneliest man in France. It is a mini-tragedy," says Dominique Moïsi, one of France's top political analysts. "The man who tried to reform did it in the wrong way and at the wrong time."