Update: The final result of the first round gave François Hollande a narrower-than-expected lead over Sarkozy. Hollande won 28.6 per cent of the vote, with Sarkozy on 27.1 per cent. Marine Le Pen won 18.1 per cent of the vote, a lower share than suggested by the exit poll but still a record result for the National Front. The Left Front's Jean-Luc Mélenchon was in fouth place on 11.1 per cent, with François Bayrou behind him on 9.1 per cent.

The official exit poll for the first round of the French presidential election has just been released and, as expected, François Hollande is on course for victory. The Socialist candidate has 28.4 per cent of the vote, with Nicolas Sarkozy trailing on 25.5 per cent, the first sitting president to lose the opening round of a French election.

Of note is the depressingly large vote for Marine Le Pen, who appears to have benefited from Sarkozy's shamelessly demagogic campaign. The poll suggests she has won 20 per cent, the highest-ever level of support for a National Front candidate. Sarkozy will hope that he can win the run-off on 6 May if enough NF voters transfer their support to him, but polls currently suggest that only 45 per cent will do so, with 12 per cent backing Hollande and the reminder abstaining.

The Left Front's Jean-Luc Mélenchon, who was in third place at one point, is currently a distant fourth with 11.7 per cent of the vote. In a boost for Hollande, he immediately urged his supporters to back the Socialist in the second round in order to defeat Sarkozy. François Bayrou, the eternal "third man" of French politics, is in fifth place on 8.5 per cent.

Based on tonight's results, Hollande is likely to become France's first Socialist president since 1995, when his mentor François Mitterand was in the Elysée. Another shift to the right by Sarkozy would risk alienating the centrist voters he needs to have any hope of victory.