That last bit is important. The Republican vote is an overwhelmingly white vote in an increasingly diverse nation. But Republican voters behave differently depending on their context. Cruz’s victory in Maine proved that he could win beyond the deep interior of the nation, and even in a state widely considered the most secular. There is an explanation for this. Cruz is winning a white electorate in states that are overwhelmingly white; Maine is one of those. Trump is winning a white electorate in states that are more diverse, like Massachusetts or Mississippi.
Groups that tend to do better economically in diverse societies have more trouble sympathizing with groups that struggle, and often tend to blame that struggle on innate traits or character faults. This is not the case in Utah. Despite being one of the whitest and most conservative states in the country, Utah implemented a simple and seemingly radical policy that has had great success in solving homelessness. Namely, Utah gave homes to the homeless. And they saved a bundle by doing so, since homelessness drives spending both in social services and the corrections department.
Another commonality of anti-Trump states is their high fertility. Utah leads the way with the highest fertility rate of all states (excluding territories), at 2.33 children per woman. The only especially high-fertility state Trump has won is Alaska, with a birth rate of 2.19. Utah is also a state in the bottom third of divorce statistics.