I grew up in East Texas; met the first Republican when I was sixteen. My mother whispered, "They're Republicans." Their daughter was John Tower's campaign manager.
My parents voted for Ike and Republican thereafter.
The Democrats in Texas were always conservative and the only ones left are "my daddy was a Democrat" types who are literally and figuretively brain dead.
I grew up in West Texas. Though it is still firmly Democratic in that area, that is primarily because of the over 80% hispanic population now. The rest of Texas, is a good example of how the political tide can change and the republicans have gained 'respectability' in areas which were formerly tight Democratic strongholds.