You may be aware of this already but just to be clear this will show up as a spoiled ballot. Write-ins have to be registered in order to count and show up in results. Spoiling a ballot is a legitimate form of electoral protest but if you want to send a more specific message you might consider researching what communist parties you can support
University of Wisconsin-Madison started an encampment today. Pretty damn good turnout of supporters protecting them as they set up in the morning. Never more than 3 cops anywhere even in sight of the protesters, and usually fewer than that (down to 0). As evening fell cops started amassing in numbers a few blocks away at a convention center and the school newspaper live reporting kept talking about how they were gearing up with full riot accoutrements to break up the camps but even as the non-campers left to go to bed there wasn't a pig in sight. Only people I know of who had any contact with police at all were counterprotesters actually. And all this after the Chancellor sent a mass email to all 50,000 fucking students saying "no camping we will make arrests." Either they're waiting till the dead of night when everyone's literally asleep or they're giving them a day or something.