Many democrats are warming to trump.
This is landslide support.
Trump has probably analyzed the electorate like any market. He will never get the entitlement class which is low education low achieving levels of the electorate, including immigrants. He also won't get the cultural elite, the self appointed American royalty on both sides of the political spectrum.
He is appealing to the middle three standard deviations of the bell curve and showing signs of doing it well.