I'm still unsatisfied with the explanation for question 4. I still think there is a strong argument that "them" refers to the editorialists. In my reading, voters pay the editorialists scant attention in their criticism of personal attacks because the voters know such attacks will end after Election Day. That final sentence still could support a reading of the sentence where "them" refers to editorialists.

Because editorialists is the subject of the preceding clause (many editorialists criticize these attacks), that draws our attention to editorialists and makes it feel more like editorialists is what "them" refers to.