One of the defining characteristics of a pseudoscience is nonfalsifiability. Although racist beliefs can certainly be made nonfalsifiable, most are simply wrong. Nor do they, usually, involve esoteric and mystical mechanisms. No one (as far as I know) argues something like “Blacks are inferior because they lack the karmic vibratory structure of the quantum consciousness that Aryans have.” Thus, it is more accurate to think of racism as junk science—if it’s science at all (most racists don’t even bother with the junk science theories of the Nazis).
But the cognitive processes that maintain racist beliefs are quite similar to those maintaining many pseudoscientific and paranormal belief systems. The major one is confirmation bias. The racist who sees a minority individual doing something bad will be more likely to remember that than if they see that same person doing something positive. Racist beliefs share another feature with paranormal ones: stereotyping. There is little difference, cognitively, between holding that African Americans have natural criminal tendencies and saying that people born under a particular astrological configuration are more aggressive.
That said, there is a big difference between the run-of-the-mill pseudoscientific belief and racist beliefs. Racists tend to be much more aggressive in asserting their beliefs, at least following the election of President Donald Trump. I doubt one would ever see a group of believers in astrology brandishing clubs and guns to attack a group of skeptics. This tendency toward more virulent and violent defense of their beliefs will make it more difficult to alter racist attitudes. The standard social psychology textbook answer to the issue of reducing stereotyping and prejudice is to have prejudiced individuals work together with members of the disliked group and so discover they’re just regular people. I doubt that approach will work in the present political climate.
What might work? Certainly being violent back won’t help—it will just egg the racists on and allow them to play the “I was a victim” card. Nor will denying them their free speech rights. They could claim, correctly, that they were being discriminated against based upon their beliefs. However, making fun of them might work. I recently saw a video of a group of Nazis demonstrating in Germany. The local citizens followed them around playing tubas and other instruments, turning the hateful parade into a sort of party and opportunity to mock the Nazis without violent confrontation.
Thinking about it, this is sort of like the anti-homeopathy events where people swallow hundreds of homeopathic sleeping pills and then … don’t die. A bit of creative energy spent coming up with different ways to mock the KKK and Nazi types could be both fun and effective.