In her victory speech Ms Royal also borrowed from President Kennedy’s 1960 inaugural address. “Ask yourself what you can do for your country,” she said.

Ms Royal, who has made no secret of her admiration for a number of Tony Blair’s reforms, is likely to come under pressure to flesh out her ideas following an unorthodox campaign that focused on values rather than substance.

But yesterday the French Left rallied behind Ms Royal, 53. She was hailed by her two defeated rivals in Thursday’s primary campaign in which 60 percent of party members opted for her highly popular but unorthodox campaign for the Elysée Palace next spring. “She won, and she won well. Everybody is behind her,” said Dominique Strauss-Kahn, the former Finance Minister who scored only 22 percent, a couple of points more than Laurent Fabius, the former Prime Minister. “The Socialists have one candidate and we have to win against the Right,” added M Strauss-Kahn.

Ms Royal, beaming and dressed in trademark white, delivered a victory speech in a solemn, statesmanlike style from her rural base at Melle, a western town where she has been MP for 18 years and regional president since 2002.

“The world has changed, France has changed. So politics must change,” she said. “I want not only to embody this deep change, but to build it with you. The French are ready for reforms. But they don’t want to have to consent to decisions that are imposed on them, without taking part in them.”

The former junior minister who has soared to stardom in the past year, emphasised that she remained devoted to the traditional left-wing cause of strengthening the welfare state. She would fight unbridled capitalism and give France’s big state administration new power to protect citizens.

She was determined to reverse the sense of decline in France. “I believe we incarnate the ambition of a France that is economically dynamic and socially united,” she said.

Commentators and party dissidents said that the woman who has enchanted public opinion with her insurgent, quirky, campaign focusing on values would soon have to flesh out ideas that often seemed contradictory. Le Monde said that she must, for example, state an opinion on the EU, over which the Socialists split in last year’s referendum on the constitution. “She has won the Socialist battle. It is now up to her to create a project for France.”

Supporters of the governing centre-Right, led by Nicolas Sarkozy, are banking on Ms Royal failing to maintain her appeal to both the old Left with her economic ideas and the conservatives, whom she is wooing with her back-to-basics values. “What gives her strength beyond the traditional Left electorate today is what might cause a loss in her own camp tomorrow,” said Le Figaro, which backs President Chirac.

Some of the Socialist old guard said that Ms Royal offered new hope for the party because she had connected directly with the public through the media and internet. “She has without question brought something new to our way of doing politics,” said Pierre Mauroy, who served as the late President Mitterrand’s first prime minister in the early 1980s. But Jean-Christophe Cambadelis, an MP close to Mr Strauss-Kahn, said that Ms Royal had killed the Socialist party.

The triumphal endorsement of Ms Royal has served as a spur to M Sarkozy and his Union for a Popular Majority. “The presidential campaign is now launched. It is high time that we united and led the UMP’s candidate to victory,” said Christian Estrosi, Minister for Regional Development.

Mr Sarkozy has been positioning himself for four years to lead the party into the elections. However, he is being harrassed by Dominique de Villepin, the Prime Minister, and by other lieutenants of Mr Chirac. The President, who is 74 next week, has even suggested that he might stand again.

POLL TIMETABLE

January 14, 2007

The governing party, Union for a Popular Movement, holds congress to choose candidate. Almost certainly Nicolas Sarkozy

April 22

First round of presidential elections

May 6

Second round

May 10

New president takes office (or President Chirac starts a third term if re-elected)

June 10

First round of parliamentary elections

June 17

Second round of parliamentary elections

June 22

New government installed

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