Sure, it can be tacked on, but it is like talking about someone illegally crossing the street to stab someone. The focus is likely to be the murder charge.
A person shooting up polling places is probably facing attempted murder (or murder if they kill someone), assault, probably terrorism charges too (since they’re trying to scare people away from polling places using lethal means). That’s a massive escalation from standing around in body armor and harassing people with questions about being a mule.