My quick thought in reading this is that we are in a very different time, with very different problems than when he was the President. Do you have some kind of specific information to support your post, that candidates are purposefully steering clear of him, or is this all just supposition on your part?

Don't understand the relevance of your post. I think the problems that have been created by this administration are polar opposite to what was going on 8+ years ago and it seems to me that the strength of the candidates running on the Republican side don't need former Presidents to back them up.