From Frank Schaeffer's commentary, "The Anatomy Of Republican Cataclysm and Democratic Victory"
Since the 1970s and in particular the Roe v. Wade Supreme Court ruling on abortion, the vocal minority of the far right of the Republican Party has fused with the far right of the evangelical movement. The evangelicals (and I spent my life as one until 1985 when I dropped out), are not a monolithic block. The evangelicals just like everyone else, are all over the map ideologically and politically. However, as with the fringes of the political parties the evangelical movement has its own far right and ultra-fundamentalist wing. These folks have taken over the power centers of American Protestant evangelical religion.
The so-called mainline denominations have been in retreat since the 1950s and all the sound and fury has been coming from fundamentalists of various denominational affiliations. To understand what has happened to the Republican Party you have to understand that the fundamentalists have, by and large, taken over the evangelical movement which itself then fused with the Republican Party.
It has taken an economic collapse, more than 4000 American war dead in an unnecessary war (Iraq), a second war we seem to be losing (Afghanistan), a meltdown of our educational system, the besmirching of our name internationally, eight years of being "led" by a born-again president who turned out to be literally unfit to govern, to finally wake the American people up to the fact that turning your government over to people motivated by fundamentalist religious conviction and/or motivated to appease fundamentalists, is an extraordinarily bad idea.
Combine all of the above with the fact that another cranky and in a way even weirder and more dangerous extreme right minority, the neoconservatives, has been cynically using and abusing the religious Republican fringe and fundamentalist base for their own purposes, and you complete the picture of disaster. The aim of the neoconservatives has been to extend and empower what they view as the imperial "destiny" of United States as interpreted through the lens out of American exceptionalism.
The neoconservatives are too worldly to believe that God has ordained American exceptionalism but they are happy to tell the rubes whatever they want to hear. The neoconservatives are our American equivalent of the old-style European empire builders such as Napoleon, who were glad to use popes or priests to bless their secular conquests when it was useful.
Read more of this interesting perspective here.