Well since the attack ads were primarily focused on his name, religion, and ethnicity, I don't think we should accept that as a rationale. I found myself unable to skip them when they played, and holy shit were they bad. His ability to attract those attack ads was almost entirely because he offended AIPAC and because he is Muslim. They tried some other tactics early on (Medicare, 'fake doctor', etc), but the last few weeks has been almost nothing but attacks on his identity.