Ms Royal, 53, who has transformed herself from minor politician to superstar over the past year, is banking on a clear majority in a vote by 218,000 members. Kind words from Bernadette Chirac, the President’s wife, and a spat over the supposed male chauvinism of her rivals, kept the spotlight on the president of the Poitou-Charentes region yesterday.

Mrs Chirac also unsettled her husband’s centre-right camp by saying that the 74-year-old President may decide in the new year to stand for a third term. “People have been jumping to conclusions. It’s far from over,” she said. According to the closest aide to Nicolas Sarkozy, the Interior Minister and expected centre-right candidate, Mr Chirac wants to run again and will try to do so if his ratings, now at a very low ebb, show signs of recovery.

Of Ms Royal, Mrs Chirac said: “You have to admit that she has a very photogenic look. Being a woman is not enough alone to win but it is important. It’s in the subconsciousness of all other women.” Ms Royal’s big lead in opinion polls may not be reflected in the vote inside a party where support remains strong for Dominique Strauss-Kahn, 57, and Laurent Fabius, 60, her two rivals.

If she fails to score at least 50 per cent the vote goes to a run-off next Thursday, which could dim her charm in the public eye. Although Ms Royal has espoused orthodox leftist positions on the economy, her emphasis on discipline and a very personal campaign have unsettled traditional socialists who see her as a closet conservative.

Six debates have shown that the relative outsider has the stature to stand up to the big beasts of the party — a former finance minister and former prime minister — but her performance has at times been shaky. Alain Duhamel, a veteran commentator who a year ago wrote off the Royal candidacy as a joke, said yesterday that he had changed his mind. The debates had shown that she had “audacity, a determination of steel, a sense of timing, a feel for the questions that people care about”. But Ms Royal had also revealed “major deficiencies in her understanding of issues — notably international — and a regrettable propensity for demagogy”.

In an unusually sharp attack on his colleague yesterday, Mr Strauss-Kahn accused Ms Royal of amateurism. “She has spent the campaign correcting and modifying. In five weeks there have been five major corrections,” he said. “I note that there are 25 weeks till the presidential election.”

He also criticised her “unworthy” accusations about the supposed male chauvinism of her rivals. On Monday Ms Royal quoted Mr Strauss-Kahn as saying after a foreign policy debate that “she would have done better to stay at home instead of reading out from her recipe cards”. Mr Strauss-Kahn said: “That is detestable. I have never said anything like that.”

Mr Fabius also rejected her complaints, saying: “You can have political disagreements . . . on certain issues, but don’t play the victim by saying, ‘Oh no, it’s not a political disagreement, it’s because of male chauvinist attitude’.”

The results of the first US-style primary by a French party should be apparent by midnight tonight.

SÉGOLÈNE ROYAL, 53

Casts herself as an outsider and new-style politician. Distrusted by party’s inner leadership. Favourite in opinion polls, thanks to deft campaign and television charisma. Promising “democratic revolution” through return to moral values, social justice and involvement of people in decision-making. Old-style leftist on economic policy. Adviser to President Mitterrand in 1980s, MP since 1988, junior minister 1997-2002, then elected president of Poitou-Charentes region. Voter approval: about 60 per cent

DOMINIQUE STRAUSS-KAHN, 57

Moderate self-styled Social Democrat offering safe pair of hands to modernise France through employer-worker consensus. Has gained popularity, emerging from television debates as reassuring statesman. Economics lecturer and lawyer who served as Finance Minister late 1990s. MP for tough northern Paris suburbs. Seen by party old guard as star of Paris chattering classes. Voter approval: about 33 per cent

LAURENT FABIUS, 60

Former market-friendly prime minister under President Mitterrand in the 1980s. Made himself over last year as champion of the “progressive” Left, a role he earned leading a “no” campaign against the party line in last year’s referendum on the EU constitution. An upper middle-class Parisian who promises to restore true socialism by soaking the wealthy to raise income of working and middle classes. He is an MP for Normandy. Voter approval: about 10 per cent

* Appproval rankings are for left-wing voters, not party members, for which figures do not exist. Primary vote is party members only.

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