John Lichfield: So what ever happened to France's Socialists?

President Nicolas Sarkozy will almost certainly run again in 2012, though he has yet to say so. Marine Le Pen said yesterday that she would mount a powerful challenge on the far-right. Centrist candidates are breeding like flies.

But what of the left? To the despair of its supporters, and even its leaders, the main French opposition, the Parti Socialiste, will spend the first 10 months of this year fighting an internal campaign to decide its champion for the spring of 2012.

The Socialist "open primary" – open to all French voters who declare they have left-wing values – will take place over two rounds in October, it was decided last week. Until then, Mr Sarkozy and Ms Le Pen will have no single, credible opponent on the social-democratic left. Some Socialist strategists fear that the party will emerge so battered that it will fail to mount a serious, presidential challenge. (The last centre left presidential victory was François Mitterrand's in 1988.)

Everyone agrees that the deeply unpopular Mr Sarkozy is beatable next year. But the Parti Socialiste is divided between a handful of nearly credible candidates. Only one is regularly predicted by opinion polls to beat Mr Sarkozy – the former finance minister and head of the International Monetary Fund, Dominique Strauss-Kahn, 61.

The primary campaign has been delayed until the summer and autumn to allow "DSK" time to decide whether he wants to leave his powerful and cushy job in Washington for the pleasures of being beaten around the head in the primary and presidential campaigns. The smart political money in Paris says that he will not run but the smart, political money is often wrong.

The only senior, declared candidate is Ségolène Royal, 57, who was defeated by Mr Sarkozy in the second round in 2007. Her early declaration has not yet recreated the band-wagon effect that she enjoyed in the less-open Socialist primaries in 2006.

That leaves, apart from younger candidates positioning themselves for 2017, the former party leader and Ms Royal's former husband, François Hollande, 56. Long dismissed as competent, sensible and dull, Mr Hollande is rising rapidly in the polls. He believes that, after Mr Sarkozy, and Ms Royal, competent, sensible and dull might be a winning ticket this time.