For a minority-majority state, TX has continued to vote pretty red. It’s a state that’s had a significant Mexican-American population for quite some time now. Blacks are and have been a minority unto themselves as a voting bloc for a whole host of reasons.
I don’t think either party can count on the “hispanic” vote over time. As the 2nd and 3rd generations of immigrant groups become assimilated into the American culture the vote tends to be less monolithic. I’ve always believed in a generation or two “hispanics” will vote pretty much the way Irish/Italian/German immigrants’ descendents vote .. which is all over the place.
One example would be the Puerto Ricans who migrated in huge numbers into NY in the 50s/60s. Half a century later, they have, as a group, risen in socio-economic status. They have intermarried; most have assimilated. They are now largely middle class. Their socio-economic status will determine how they vote more than their demographic. Most Puerto Ricans I knew personally were more conservative than I ever dreamed to be!
So, I am not going to buy into the doom and gloom scenario for the GOP and/or Euro-Americans being some hopelessly out of power minority.
Texas has only been a minority-majority state for a few years and in that time the margins between Republican and Democratic voting margins margins have narrowed. Furthermore, the urban and suburban whites in Texas are trending Democrat and Obama won the major cites of Texas in 2008.
In ten years the trends are likely to more dramatic and it is going to be very difficult for the GOP to hold Texas.