[Example: President Trump should have a 70% approval rating based on his performance. That he is barely treading water is no accident - at least half of the electorate has been completely brainwashed]
I am nor sure they are all brainwashed. I think some are not really convinced by the brainwashing but will vote against Trump anyway. Some of this is not even a matter of truth. If a leftist believes that it was "Hillary's turn" in 2016, that is just an opinion, but such an opinion is pretty much outside the realm of facts. Others believe the lies.
Remember, a lot of secret Trump supporters out there.