Since people make up religious groups as well as political parties in the US, I don't see how one can limit their influence, except through the checks and balances of a democratic government.

In my opinion, the media greatly exagerates the influence of the Christian right, as well as the differences (not to mention the Hollywood-type gossip) generated by a political race. And it LOVES to feed on the extreme views regarding any social issue. We mustn't forget that there are alot of folks in government (from the local and state level up to the national level which includes many senators and representatives) which are there for precisely this reason: so that no one group would have control over the government of the United States. Infact, if American were run by Christian Fundamentalists, we'd be living in a totally different society.....

From Wikkipedia: