True, Pantglas, I think that people who run for high office must start off with an inflated sense of self to some degree. As I look at the whole group and pare down, OUT are those who are persistently, primarily and/or exceptionally:
1) intolerant/exclusionary (racists, misogynists, blatant classists, etc.)
2) abusive/divisive
3) self-serving (narcissists, liars, financial opportunists, etc.)
4) unscrupulous (apologists and cronies of the corrupt, lobbyists for those who put their financial bottom line over public welfare, etc.)
5) ignorant (science deniers, those who show no desire to learn about or understand the world around them)
Then I look at the focus and plans of each remaining candidate and go from there. Easy-peasy, right? It often ends up being a "lessor of two evils" type of thing but one can only work with what's available.