That struck me as a prediction of violence not a threat of violence.
Similar, I suppose, to the nutjob in Nevada who predicted that some people would resort to "second amendment remedies" in the event Reid was reelected.
But to your point, we are by nature a bloodthirsty people, republicans and democrats. Does this sound familiar:
For from this hour, we will bear it no more, our rights shall no more be trampled on with impunity. The man or the set of men, who attempts it, does it at the expense of their lives. And that mob that comes on us to disturb us; it shall be between us and them a war of extermination; for we will follow them till the last drop of their blood is spilled, or else they will have to exterminate us: for we will carry the seat of war to their own houses, and their own families, and one party or the other shall be utterly destroyed.—Remember it then all MEN.