One of the things that most amazes me about hard-right conservatives is their (self-serving) belief that the Founding Fathers never actually intended for there to be any real or significant separation between the church and the state. This link gives a good summary of their position. Basically, they believe that the First Amendment means only that no national religion may be established, and that no "sectarian policy" be pushed on the federal government or any individual state. They seem to envision a better world in which public school children are preached at constantly, and with Ten Commandments monuments marking every bit of public land. (One wonders if Muslim and Buddhist teachers would have the same freedom to talk about their religion, and if Pagan monuments would be as welcome as Ten Commandments ones, but of course they'd probably get around that little issue by falling back on the old chestnut that "this is a Christian country," thus neatly limiting religious freedom only to those they agree with.)
What I really find amusing here is the contention that the ACLU has used the First Amendment to "tell pastors that they do not have the right to speak freely from their pulpits applying Scripture and church teaching to candidates and elections." I don't believe anyone's ever argued that. Churches aren't "public" in the sense that they're on government land. That's obvious. But tax-exempt institutions can't make political endorsements, which seems perfectly reasonable to me. If churches don't like this, there's a simple way around it-- start paying taxes, and then the government can't tell you what to do.