The polls were right: the first round of France’s presidential election came out just as they said. Centre-right candidate Nicolas Sarkozy is on top with 31.1%; Socialist Segolene Royal was a respectable second with 25.8%. French voters must now choose between them in the second round on 6 May.

Francois Bayrou of the centrist UDF was third with 18.5%: a huge jump from the 6.8% he won in 2002, but not enough to overtake Royal. (Official results here.) The far-right’s Jean-Marie Le Pen was well back on 10.5%; then another big gap to fifth place-getter, Trotskyist Olivier Besancenot, on 4.1%. Turnout was a very high 84.6%.

Royal’s task in the runoff is going to be difficult. Total vote for the seven assorted left candidates came to about 36.5%, against 45% for the right. Comparing those totals with 2002, when both sides were around 46-47%, it appears Bayrou’s increased vote has come at the expense of the left.

So far, Bayrou has avoided giving any endorsement, but unless Royal can pick up the majority of the centrist’s supporters, Sarkozy looks set for a reasonably comfortable victory. An opinion poll last night showed him leading Royal 54%-46%.

After the shock of 2002, when Le Pen sneaked into the second round at the expense of the Socialists, this election has seen a swing back to the major parties. The two front-runners had a majority of the first-round vote between them, whereas in 2002 it was only 36.7%. All the minor candidates lost votes; the once-mighty French Communist Party is down to just 1.9%.

Bayrou’s strong showing nonetheless heralds a possible shake-up of the party system. The expectation had been that whichever party won the presidency would also win a solid majority in the legislative elections, to be held in June. (The elections were deliberately aligned in order to achieve that.) But if the UDF can maintain its support until then, it may well emerge with the balance of power.

In the meantime, France must decide whether it prefers the hard-nosed reformist populism of Sarkozy, or the more gradualist program of Royal. It should be an interesting fortnight.