@Demosthenes I think it is both, but much of the right completely rejects they have any racist thoughts. People are defining racism differently is part of the problem.
I also think it is chicken and egg as you discussed with @hello321. Imagine a lot of Swedes and Germans came pouring into the country. Probably true the alt-right wouldn’t pay attention unless some Fox News or radio guy pointed out they are likely 80% Democrats.
Look at Texas, a lot of people coming from California and Texans are worried about them being Democrats. These are our countrymen. Probably a lot of white Americans making the move.