This does not surprise me, nor is it likely to change regardless what happens in the future. It’s how people are. Support for Nixon remained at 30%+ after he resigned. Support for McCarthy remained at 30%+ even after he was thoroughly disgraced. Why do people do that? Seriously, why do some people continue to support a repugnant person even after the evidence, sometimes even proof, is blindingly obvious?
I suspect there are a couple reasons, not necessarily mutually exclusive. One, there will always be people that simply agree with the person’s ideology. Which isn’t automatically a bad thing, it’s just the blind extremism that starts the problems. And really, this shouldn’t come as a surprise to anyone, and there’s no need to act all incredulous over it. These people who never waiver believe that the end justifies the means.
But, two, and I think this one runs deeper within the person and yet more shallow at the same time, to many of these people to admit that the person they’ve been following is wrong would be to admit that they were wrong. And, well, we just can’t have that. They’ve invested themselves into it. That would be admitting that they are somehow flawed in their thinking. That would be akin to admitting that maybe others have a better handle on the issues than they do. This would hold especially true for those who have roundly ridiculed the other side for so long. Their own base reputation is at stake. So, no, human nature and pride does not allow those deepest in to admit so publicly.
It’s not going to change and go down farther. Those who would never support Trump no matter what already oppose him. Those who exhibit something that at least mimics an open mind, whose who agree with some aspects but not all or who were lost, are now against him. That leave those who will always support the man no matter what, those who are pretty much mirror images of those who will never support him.