Even then, I'm guessing they'll still dismiss it as a few lone wolfs within a "hateful minority" that's generally too small to worry about — rather than a larger, far more systemic problem the Left has in general (which is exactly why they get away with it so much).
You know, kind of like Muslims blaming "a few fanatics" for Islamic extremism ... without acknowledging there are tenants of Islam itself that make members of their community more likely to commit violent or extrajudicial acts in the name of their faith than Christians or Jews are, for example. Not saying individual Muslims are to blame for everything the wackos do; merely pointing out that certain teachings beget certain behaviors, especially from loonies on the edge already. Unfortunately, the Left has no shortage of those, either.