@eal The four main favorites are E. Macron (center-right), M. Le Pen (far right), F. Fillon (right), J.L. Mélenchon (left). The last polls before the elections tended to give the candidates in that order for the first round.

A poll by the french-speaking belgian tv RTBF done at midday among people who just voted gave that order too apparently. French broadcasters cannot publish results of any poll before 20:00, so a way to know the results of those polls is to look at news from neighbouring countries (Belgium and Switzerland notably).