Maybe instead of resorting to exaggerated dismissals and suggesting I lack sanity, think about it for a minute because I think once you do, it's pretty obvious.
What they should do about it is use it to win and keep Trump out of the White House. If they turn it into a criminal law issue it'll confuse the matter and turn what should be an argument about right vs. wrong into legal vs. illegal. There exists a realm of behavior, quite a large realm in fact, of things that are deplorable but not illegal. Such as waving an ISIS flag, or walking around in a Hitler moustache and armband. That's where Trump's behavior fits.
This is why when a Nazi gets criticized, the first thing they do is cry "free speech". Because by making it a legal matter, they're picking the best hill for them to fight on. They skip the question of whether their behavior is reprehensible, and fight a battle they can win - whether it's legal.
So if you want to do Trump the biggest favor imaginable, decide to fight this in the courts. Make the question "Is it legal to be racist" because we all know the answer is yes, and even if it wasn't the courts (especially in red Ohio) are heavily in Trump's favor and have repeatedly shown willingness to help him out. That way we can have a dismissal and headlines "Trump wins again" and pictures of him with a big smile on his face. See: Just about every past time Trump has been brought to court, or charged with impeachment.