John Lichfield: Le Pen's six million supporters hold the key to the Elysée

Can Nicolas Sarkozy still win? "Arithmetically, it is just possible. In terms of electoral mood and practical politics, it's probably beyond him," a senior figure on the right of French politics told The Independent yesterday.

Much depends on the 6.4 million people who voted for the National Front candidate, Marine Le Pen, on Sunday. In terms of votes cast, this is the highest total ever recorded for a far-right candidate in a modern French election. Ms Le Pen took 1.6 million more votes than her father Jean-Marie Le Pen attracted when he reached the second round 10 years ago.

Such a huge score for a xenophobic, anti-European, anti-establishment party poses awkward questions about the health of the French and European political systems. It presages a possible re-drawing of party and ideological boundaries on the French right if a defeat for Mr Sarkozy next month shreds his centre-right UMP.

To win the second round on 6 May, Mr Sarkozy has to claim most of Ms Le Pen's votes and two-thirds of the three million people who voted for the centrist candidate, François Bayrou. Opinion polls suggest he will take only six in 10 of the Le Pen voters and two in five Bayrou voters. President Sarkozy made it clear yesterday that he would vigorously pursue the hard-right vote and would step up his rhetoric on immigration, crime, the failures of the EU and the supposed Islamic threat to French "national identity". But he immediately faces two problems.

The more Mr Sarkozy talks the talk of the far right, the more he alienates centrist voters (one-third of whom are already thinking of voting for Hollande). Secondly, far-right voters are not a monolithic block.

Many of the "new" voters attracted by Ms Le Pen on Sunday were from rural areas of the west which have been relatively immune until now to the charms of the NF. These are mostly conservative voters angered by falling incomes and reduced rural services. They may go back to the President on 6 May. Ms Le Pen also attracted new blue-collar voters in the industrial east or north who were also considering a vote for the anti-European far-left candidate, Jean-Luc Mélenchon.

Many of these voters will probably turn to Mr Hollande on 6 May or not vote at all. The third group of NF voters – the 10 per cent of the electorate which forms an ultra-nationalist hard core – also detests Mr Sarkozy. Many will follow Ms Le Pen's advice and abstain.

The arithmetic of the projected votes in our graphic suggests a narrow victory for Mr Hollande. Opinion polls put him between six and 12 points ahead. "Unless Hollande makes a serious blunder, he should win," the senior figure on the right said.