On Sunday (22 April) French voters will cast ballots in the first round of the presidential election. As media in France are banned from announcing results until 20:00 local time, all eyes will turn to the French-language media in Belgium and Switzerland, which will unveil exit poll results as early as 18:00.

The French election is seen as a potential game-changer for the European Union.

If France turns left, as opinion polls indicate, the near-monopoly of the centre-right European People's Party in Europe would be broken.

In case of another mandate for French President Nicolas Sarkozy, Europe could move faster towards a two-speed Union and a revamp of the bloc's Schengen area that could see Greece excluded from the passport-free travel zone and further EU enlargement frozen.

As part of a series, EurActiv France has produced profiles of all major candidates and analysed their stances on European issues (order of appearance reflects latest opinion poll ratings):

Early results from exit polls are expected as early as 18:00, both for the first round and the 6 May run-off.

But because French media are prohibited from making any announcement before 20:00, millions of French people are expected to zap, tune in or log into foreign French-language news media in Belgium and Switzerland, which are not bound by such constraints.

Two-horse race

According to opinion polls, the conservative incumbent Sarkozy and Socialist candidate François Hollande have the biggest chances of making to the 6 May run-off.

Both are running neck-and-neck for the first round, with 27-28% of the votes each, the latest opinion polls show.

However, two other contenders have emerged as a potential "third man".

Far-right candidate Marine Le Pen is credited with 16.5% of voting intentions and has been on the rise in recent days. On the other extreme of the political spectrum is Jean-Luc Mélenchon, who appears likely to become the biggest revelation of this election.

Mélenchon's flamboyant anti-capitalist rhetoric has won him the reputation of "a new Robespierre" in the French political media. He is credited with 14% of voting intentions, but his electorate appears very motivated and surprises may occur, especially if turnout is low.

The centre – and the rest

François Bayrou is the only centrist but according to analysts, his declining ratings, around 10%, appear to indicate that the political centre is not fashionable in France these days.

The remaining five candidates are unlikely to make a big difference.

Eva Joly, a Norwegian-born magistrate running for the Green party, is credited with only 2.5% of voting intentions, despite the party's good score at the 2009 European elections, with 16.28% of votes.

On the extreme left are Nathalie Arthaud from Lutte Ouvrière, a French Trotskist  party, and Philippe Poutou from the New Anti-capitalist Party. Nicolas Dupont-Aignan is a sovereignist and Jacques Cheminade is a maverick politician running for president for the second time, after having scored 0.27% in 1995.