"An alternative way to make inroads into the overwhelming majority of minority votes for Democrats would be for the Republicans to articulate a coherent case for their principles and the benefits that those principles offer to all Americans."
Principles that benefit all Americans... Some dupes might expect that to be a popular idea, but that is a concept that most people are not motivated by. How many people does one encounter who mainly vote for causes that do not benefit them personally? I have not seen many, and that is for certain.