Actually the Socialists likely won't make the second round and in the last election it was between the Socialist and UMP (centre-right).  This upcoming election it is true the National Front will likely make the second round, but their opponent will be either Les Republicains (Centre-left) or En Marche (Centre).  The Socialist Party is so unpopular even with their new maverick leader I would be quite shocked if they make the second round, mind you with the Filion scandal and Macron having a vague platform I guess anything is possible.