Exactly about 25% abstained from voting and about 8-9% spoiled their ballots, effectively creating a 16 million strong uninterested/spoiler block. Another indicator that all is not as it is portrayed by the establishment media is that Le Pen won the 18-24 demographic. 

Marcon should be mostly seen as a vote for the most palatable choice and an outcome of tactical voting as opposed to any sort of endorsement of a political program and vision. France like the rest of EU is seeing the collapse of the political centre and is moving more to the "right" (watch out for the parliamentary elections). If anything Le Pen's result indicates that there is a lot more traction for her ideas and political program than many is prepared to admit. If Fillon can recover from his own goal, something not too different from the UK might be slowly on the cards for France (Torries rediscovering their patriotic working class constituency...)