Portillo writes (I use the term loosely) for low subscription newspaper read predominately, but with again limited distribution, in the town of Tucson. He likes to preach to the choir of fhe large illegal hispanic population (and their advocates)who reside there in significant numbers.
Only problem for Ernesto is the illegals don't read the newspaper, especially the The Arizona Daily Red Star.
Not that I've done any scientific polls, but among my friends and acquaintances opinions aren't split on anglo/hispanic lines, but on liberal/conservative lines. Many hispanics oppose any special treatment of illegals (other than getting them out of here), but sadly their voices are rarely heard.
Obviously a minority of hispanics are politically conservative, so your point is essentially on the mark.