Then you recalled very wrong.
Just look at US Senate and Presidential election results. These elections are voted at large so it counts everyone's votes equally no districts.
https://en.wikipedia.org/wiki/United_States_presidential_elections_in_Texas
As you can see every single presidential since Reagan was a Republican win in Texas. Majorities ranging between +3% to +27%, last election Trump won 56% of the vote.
I'm not saying the state isn't gerrymandered, it definitely is, most states are. But it's certainly not a majority Blue state at least historically. I'm hoping for a major upset this election cycle