It very well could be that I am drawing a hasty generalization. But I have been watching politics closely for 30 years. Since the 1996 campaign, I have seen an interesting phenomenon: Democrats spent a lot of time trying to convince non-Democrats they should change their minds; Republicans spent a lot of time just talking to their base. This worked sometimes for both sides.
Now, however, I am beginning to wonder if always talking to those who agree with you is not beginning to harm the Republicans structurally. Ironically, the news channel most associated with the right is Fox News… talking mostly to those who agree with you already–working only in the domain you know really well-should maybe be called Hedgehog News.