The re-emergence of the hardcore communist left, led by Mélanchon, and other far left groups like the greens and ecologists, who have a long tradition of anti-Semitism, anti-Zionism and support for the Muslims and Palestinians is a huge problem for Hollande.
Hollande must unite these fringe far leftist groups to win, and include them in his government if he wins, which is likely.
Israel will no longer have a friend and supporter in France, and the groups that demonstrate for the end if Israel, and are behind the BDS movements around the world, the Gaza flotilla, etc will be in power in France.
What can be said? We just have to wait and wonder if the world is going to go on fire yet again...