He didn't have a choice in that one, not unless they were willing to forego all of the Texas electoral votes.
The point is that voting registrations can be quite fluid, depending on what works into one’s political convenience. I don’t want to get into attacking Liz Cheney but I really don’t like what she’s doing here. It reeks of opportunism, taking advantage of family connections without having a really strong personal connection from having lived in and been part of the state herself within recent memory. Has she ever lived in WY as an adult?