Religious bigotry? Hardly.
As a Bishop in his church, Mr Romney no doubt believes in Kolob, either as a physical place or a metaphorical concept. The bumper sticker may be ironic, or even satirical, but it is certainly not bigoted.
Now, calling Obama a Muslim, particularly when that characterization is meant as a deliberate insult to both Obama and Muslims, is clearly religious bigotry. Your party did that even though it wasn't backed into any corner at all.
Your crowd also called Obama a a foreigner and a Socialist, but you can't really call that religious bigotry. It's just plain old bigotry.