Additional discussion, on-going, in the other thread (prematurely titled “Scott Walker is in”).
Wow. That was quick, but not at all unexpected. 
what was really great was hearing commentators say “who gets his support,” but then someone else saying “he polled at zero, he has none.”
That wasn’t premature, that was a direct quote from Walker when he announced his candidacy a little over 2 months ago.
The question was never “who WILL get Walker’s supporters,” it’s “Who already GOT them?”
Walker was running as a tight borders guy. That was his big issue. Donald Trump took that issue and ran with it. In the process, he took almost everyone who liked or MIGHT have liked Walker.