Hillary Clinton claims Democrats cannot be civil with Republicans until Democrats once again run everything in Washington, DC. Mad Maxine Waters urges Democrats to get in Republican's faces. Eric Holder advocates kicking Republicans when they're down. Other visible Democrats have voiced similar intemperate sentiments. And the crazies of Antifa barricade streets in Portland, harassing drivers and damaging property.
Democrats haven't done a lot of winning lately and it's making them irrational. Mob behavior and (at least the threat of) violence seem to be the order of the day for our former friends on the left. We saw quite a bit of that in the halls of Congress recently during the Kavanaugh hearings, with many arrested.
None of this is a reason to vote for Democrat candidates, whereas it can reasonably be viewed as a reason to vote against them. Do you recollect Republicans doing any of this during the Obama sweep of 2008? I sure don't, and I was paying attention, too.
American politics, properly pursued, is not a contact sport. Beating on people and screaming at them are prima facie reasons to oppose whoever is doing that hateful behavior, to vote against their chosen candidates.