When French presidential contender François Fillon marked the Feast of the Assumption last summer, he attended Mass at Solesmes Abbey, a Benedictine monastery known for resisting the anticlerical purges of the French Revolution. The trip, coming just weeks after the slaying of a Catholic priest in a terror attack, didn’t go unnoticed.

“He doesn’t hide the fact that he’s Catholic,” said Christophe Billan, head of Sens Commun, a grass-roots movement comprising thousands of French Catholics.

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