During one of the great speeches in recent history Robert F. Kennedy implored Americans to get involved in the political process and also said this:

"And so I am going to tell you this, that the next time you see John Stossel or Glenn Beck or Rush Limbaugh or Sean Hannity --- these flat-earthers, these corporate toadies, lying to you, lying to the American public, and telling you that global warming doesn't exist --- you send an email to their advertisers and tell them that you are not going to buy their products anymore." This mashup evidences who you should be writing to and boycotting.