Earlier quoted context omitted.
...the fringes... Who is this? How can I tell who of my neighbors is in this group? Having made that determination, how should I treat those neighbors?
This seems akin to feigned disbelief - you know the answers to these questions but are pretending not to. I'll bite anyway! > Who is this? How can I tell who of my neighbors is in this group? People who espouse beliefs far away from the median belief in the society. You can tell by taking to them about their beliefs, or often in my experience by having them talk at you about them or by looking at bumper stickers and…
Second, the proposed method of making this identification is entirely subjective. I'm planning to vote either Green or Libertarian this election, because I oppose war, prohibition, and other travesties of the status quo. On the topics of most concern to me, I literally can't tell the difference between Clinton supporters and Trump supporters. How can I determine whose "sins" I should "hate"? Perhaps I should hate my own sins, even though they couldn't possibly be of support to Trump? This is quite disturbing to me, and the principle of charity had previously ruled out this reading of OP.
With the same kindness you treat everyone else, but without having to agree (or pretend to agree) with our have any respect for their views. You "hate the sin, not the sinner".
Incidentally, if any particular campaign takes this particular idiotic rhetorical stance, and then loses, and then wonders why? They'll be able to blame this particular idiotic rhetorical stance. In order to convince people of anything, one must speak with fluency in the people's terms. Your use of "sin" here would not be considered idiomatic by any Trump supporter I know.