That's presumptuous as well. How do you know that anyone is going to do that and not decide to do whatever the majority want, irrespective of their own beliefs and faith?
Answer: You don't. You are presuming.
A truly religious person puts his religious law above secular law.
A person who votes against the position of his religion because his constituents wanted it is not truly religious. In fact it's very hard/impossible for a truly religious person to enter secular government in the first place. True adherents do not make compromises. They do not breach divine law.
If your allegiance is to secular authority first and your religion second, you aren't a true follower. Is this not apparent?

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