It's an issue that he has to deal with, one way or the other. He can no longer dance around.
Besides, church goers would never vote for him any way. They'd rather follow their pastors and preists. This may energize GOP base. But it may energize Dem's base even more.
Independents would not pay as much attention to social issues. Given time, they will also shift their positions because, when people think through, rationale trumps religious believes.
It's a risky move, though. But American voters tend to respect those who take risks and stand their ground.