Given the disaster of the Hollande administration, the current weak state of LR, and the ongoing problems with the European Union, it's no surprise that the far-right has become quite powerful in France. I would caution against underestimating Le Pen.
This could be a real opportunity for Hollande. If he really orders the police to go in heavy and start cracking heads, he could have a 9/11-style rally effect and boost the center-left. But like most center-leftists, he is an idiot will probably do nothing and hand the country over to Le Pen.