I could never vote for someone who is a devout Muslim.
It depends on your definition of "Devout". For me, a devout Muslim is someone who goes to Mosque, celebrates his religious holiday's, reads the Koran before bed. A Muslim, especially in Western society, that campaigns to implement Sharia Law and Caliphate-like system of rule is a radical.

I would vote for a devout Muslim, should his views be something I agree with.