Normally, I'd say this isn't really that big a deal. Not very classy, to be sure. Not something I would expect from a professional and supposedly unbiased journalist working for CNN... oh, wait. I would expect it from a professional journalist working for CNN because CNN is about as biased as you can get.
But remember when the left went after Palin for putting "crosshairs" on a map of a Congressional district where Gabby Giffords was later shot by a crazy vaguely-left lunatic? And remember when an assassin tried to murder everyone at a Republican Congressional baseball team practice? Or Rand Paul's neighbor violently attacked him?