The interesting thing about Bush/Clinton/Trump is that Trump is more popular with relatively center-right voters than hardline conservatives. He is the new Perot in a lot of ways (in a country that's shifted quite a bit to the left since '92).
Yes, in fact even in the primary part of this poll, he does slightly better among "moderates" than "conservatives". It's Carson, Cruz, and Huckabee who are relying more on the self-described "very conservative" voters.Partially serves to confirm a theory of mine; going left on immigration actually hurts Republicans more than it helps. Within the GOP the ones who are in favor of it are generally wealthy businesspeople (the GOP's most consistent "base" group since its founding in 1854), while I would expect (moderate || swing || persuadable) voters, generally middle-class whites who do not attend church weekly, to be pretty strongly opposed.