Whenever a Republican comes along without a clear conservative pedigree, the self-appointed guardians of the movement seek to measure whether he is a "true conservative" or just a big-government apostate hiding behind the R label. Donald Trump garnered more than his share of suspicion - some of it for good reasons (past campaign contributions to Democrats, past liberal policy positions), some of it for silly reasons, like the words he uses and so forth.
Most of the time, though, a candidate's "true conservative" bona fides get measured on the basis of things like abortion, spending and taxes. All of those have some importance, but for my money conservatives tend to place way too little value on regulation as a way of assessing a candidate's conservatism, especially when that candidate is running for president.
