Here’s my comment on the FN’s political chances:
http://www.freerepublic.com/focus/news/3607050/posts?page=7#7
I’d add that, with Macron being a nimble politician, even chameleon-like, barring some scandal or bungled national tragedy on his watch, he’ll probably be reelected by a huge margin, leaving the FN marginalized, but perhaps still in second place.
Notice the East-West gradient in those maps. The West of France is rural and has few immigrants. It’s also the area where anti-clericism was highest, so people there are less religious.