Donald Trump's approval rating doesn't even accurately reflect Donald Trump's actual approval rating. It's an extremely unreliable statistic as there is evidence that his supporters have denied supporting him in the past.

There are also plenty of racist people who identify as democrats or independents. There are people who are racist and smart enough to recognize that Donald Trump is absolutely wrecking the economy.

Also, what about people who have absorbed highly biased media information without the ability to effectively select a different source of information? Let's say you're talking about a 90 year old woman who can barely hear or see, but she does her best to remain reformed. She can't adequately evaluate her media sources, and so she only watches Fox News coverage. The reporting coming from Fox doesn't provide information about Trump that would cast him as a racist. And this woman can't even pick up all the information coming from Fox, all she really hears is that Trump is doing a great job.

In a case like this, it's possible to say a person supports racist policies without supporting a racist.