Eventually, the crazy kills the host.

Ed Kilgore nails it.

My aim here isn’t to identify the national Republican Party or the conservative movement with the exact utterances of its zaniest members, but simply to say that they can’t encourage or embrace extremist premises and then reject as alien entirely plausible applications of these premises just because they sound crazy to swing voters. If you want to marginalize pols like Todd Akin, don’t keep saying you are absolutely certain that as a matter of divine, natural and constitutional law, human life begins at conception. If you don’t want to get blamed for Tom Head, stop acting as though private property rights came down from Mount Sinai, and cool your jets a bit about American Exceptionalism.