Ségolène Royal, the runner-up for the French presidency last year, savoured revenge yesterday when she took a surprise lead in a bitter race for leadership of the battered Socialist Party.

Ms Royal, 55, who has undergone a make-over and acquired a new boyfriend, gathered enough grassroots support to emerge four points ahead of Bertrand Delanoë, the Mayor of Paris and the favourite, in a key vote before a party congress. Mr Delanoë, 58, scored 25 per cent, as did Martine Aubry, 57, the Mayor of Lille and a former Cabinet minister.

The contest is personal because Mr Delanoë is backed by François Hollande, the outgoing leader who was Ms Royal’s domestic partner for two decades until their acrimonious split last year. Ms Royal, who is the subject of a whispering campaign about her mental state, blamed Mr Hollande and party elders for her presidential defeat, while they depicted her evangelist-style campaign as chaotic.

Ms Royal, the mother of Mr Hollande’s three children, has cast herself as the wronged woman, attacking her former partner for leaving her for a magazine journalist. She has just scored another kind of revenge against the plump, 54-year-old party leader by going public this week with a handsome, younger new partner — Bruno Gaccio, a 48-year-old television personality.

She warned her colleagues that she had the whip hand after the preliminary backing in the vote among the 220,000 party membership. “This gives me new legitimacy. The vote will have to be respected,” she said.

The congress, in Rheims next weekend, is supposed to crown a saviour for France’s main opposition party, which has been in the doldrums since Nicolas Sarkozy beat Ms Royal last year.

Mr Sarkozy’s centre-right UMP Party mocked the Socialist civil war, saying that the vote “reflects the immense confusion” of the opposition party. Mr Sarkozy is enjoying new popularity with his handling of the financial crisis. His approval ratings have turned positive for the first time since December 2007. On the other side, the Socialists, who have lost three presidential elections in a row, are being squeezed on the left by Olivier Besancenot, a charismatic young Trotskyite, who is drawing strong support for a fledgeling New Anti-Capitalist Party.

Ms Royal, who holds no party office, has rekindled some of the excitement that she generated last year. She has managed this by shifting leftwards and casting herself as a scourge of capitalism — a role that she tried out with a glitzy one-woman show at a Paris rock venue in September. Her bizarre performance there, between stand-up comedian and TV evangelist, prompted suggestions from the Hollande clan that she needed psychiatric help.

Ms Royal is seeking alliances with rivals in the run-up to the Rheims congress but none of the main contenders has been ready to back her. With Mr Hollande’s support, Mr Delanoë is expected to fight to the end.

The resentment towards Ms Royal could breed a “stop-Ségolène” coalition with a compromise figure at its head. It was also not certain that

Ms Royal would persist in claiming the leadership, as her main aim is a rematch against Mr Sarkozy in 2012.

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