It depends on who you ask.
In my opinion, any state could hypothetically secede and just dare the federal government to send in an army. That won't end well of course, but Texas seceding could set off a domino effect that results in it actually becoming a "well, better to just let them go do whatever" situation.
But most people will say "lol, secession isn't legal". Why? Uhhhhh something something civil war.
You'd think that Congress would have gotten an amendment saying "lol can't seceed" during or after the civil war, but they didn't. There was just a supreme court case that said "lol confederacy lost", and little else.