This number comes from a company called ARC of Washington. They are known as Advocates for the rights of citizens. They are a non-profit donations group. They also have a 1-800-826-4310 number they give out as well. I called them and asked to be taken off their list, I hope that helps.
They just don't get it. Arc of Washington calls me morning, noon, night, and now weekends. They don't say anything, just hang up after my answering machine says i don't donate over the phone or talk to telemarketers. I have sent emails and phone messages to them over the years to stop and they don't. I am thinking of taking a film crew to their Olympia headquarters and serving them with a harrassment complaint. I tried blocking them and a thousand other numbers from them or their county proxies come through. I think that getting their 501c3 status removed and funding cut is the next step.