White supremacy isn't about you, or about your candidate
It's a big problem we have as white progressives, this desire to "not be racist"; we end up making every discussion of race about us when it probably shouldn't be.
When I was growing up in the 1980s we had black history programs in my small town Mississippi public school every February where we would re-enact scenes from black history. As one of the few non-black students, I was always portraying Matthew Henson (because I could wear a parka that covered my face -- look him up some time if you don't know him). I did once play Bull Connor, now that I think of it, but they decided not to do that again. (This is complicated by the fact that I was "insufficiently white" to go to the private school, and we couldn't afford it anyways -- race is complex sometimes in mixed families, though I claim "whiteness" now, and now that I'm in India whiteness is thrust upon me.)
Unlike my tenuous racial definition, my wife is unambiguously a "woman of color", from the Indian diaspora in the US. I've learned a lot about race and racism in the US from listening to her. And since the time I've known her corresponds pretty exactly with the time since I've banished sentences starting with "Well, actually..." from my speech (this is probably not a coincidence), I've been better at listening to her than I have to most people before.
Anyways, my point is that one thing I've learned is that it's always a bad idea, as a white person, to make a racial conversation be "about" you. If someone is talking about race, the question "how can I avoid being racist?" should be the least important one to you. It should be unimportant to you because the whole point of being white is that you don't have to think about race at all if you don't want to. Plenty of white people say, "well, I don't see color". And that's exactly right: whiteness is a free ticket to not see color any time you don't want to. This is why whiteness has proven so malleable over time: Iberians and Irish people did not have it 100 years ago. East Asians are in some ways gaining it today (though there's still a long way to go there); South Asians were until the War on Terror put crosshairs on them.
Those of us born in the 70s and 80s grew up in a time when racism as a personal view was starting not to be socially acceptable. Even in the Deep South, people who held avowed prejudiced views would concede that it was a social faux pas to admit them, and in many cases that they themselves are somehow atavistic and holding views that society has left behind. That was our model of racism and white supremacy (I don't see a meaningful distinction between the two terms, personally, so I'll stick with "white supremacy" from here on): white supremacists were bad people, morally flawed in some way, and if they would simply be more moral (or just die off) then white supremacism would end and all people would be judged by the content of their character, blah blah blah.
And that was probably the right message for the time, when individuals' prejudices were a huge part of the struggles people of color faced. The threat has changed in the years since, though, and we are in the era that's misleadingly called racism without racists. Action requires agent, so clearly it's not the case that today's racism is without racists, but the view we are stuck with of racism as a moral failing rather than a structural power imbalance makes the "without racists" tag the only way to get that message across without people screaming (and even with it, people scream).
If a segment of the white Left says "there is no difference between corporatist Democrats and corporatist Republicans", that can sound to many people of color like they are saying that the differences that do exist, on criminal justice, the minimum wage, housing policy, education, lead abatement, etc., don't really "count". Straight white males may in fact not see much of a difference between Republicans and Democrats; that's our privilege. FHA rule changes don't determine where I can and can't buy a house (not that I can buy a house, but you get my point). DoJ-led reviews and reforms of metropolitan police departments don't noticably change my level of risk when I go to the corner store. If a segment of the Democratic party praises the economy of the 1950's, even though everybody knows they mean in their hearts "but we'll all be like the straight white males were back then!", it can sound very tone deaf.
And that, when it comes down to it, is white supremacy. The headstrong faith that the New Deal, the Great Society, the 2.5 kids and white picket fence in a cul de sac paid for by a single earner with a good Union job, can be trivially granted to the people on whose backs it was built without fundamental re-imagination and explicit prioritization of people of color. That cul de sac neighborhood? Redlined. That good Union job? Official discrimination was ended by the AFL in the 1960s, but unofficially it lasted much longer in many shops. The schools those 2.5 kids went to? Paid for by wage and tax theft from the darker people in the poorer neighborhood. If you don't start your wishlist with addressing the racism that made this theft possible, you're going to repeat it whether you mean to or not.
Whoever the next President is, he or she will probably not determine much of the national agenda. The 218th Representative and 51st Senator will. This may have something to do with why, time and time again, voters have shown that they don't really vote for people based on policies; they are not electing a set of ideas to the White House but an actual human being that they do or don't feel a connection with, and whom they do or don't feel understands them and their problems.
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