Saqib Ali, an American politician and a Muslim, supports gay marriage. Not personally - it goes against his faith. But he understands that his job as a legislator is to represent his constituents and to uphold democratic values.
In an editorial, Ali says "If I tried to enforce religion by law — as in a theocracy — I would be doing a disservice to my both constituents and to my religion." So, as a legislative policy, he supports extending marriage rights to same-sex couples. He is not subverting his values to those of the society he finds himself in. He is simply finding a path that allows him to stay true to his values, while upholding his responsibility to the people he represents. (There are many ways to oppose gay marriage without making it illegal; just as there are many ways to oppose abortions without making them illegal.)
Thanks to the Friendly Atheist for making me aware of this.