Oh I really hope Cruz will get destroyed by this guy. I have no faith in it but I really hope he does.
Texas' demographics are changing, and Republicans are fleeing the GOP there.
Consider: the quintessential swing state in Presidential elections is Ohio.
1992: Clinton +2
1996: Clinton +6
2000: Bush +3.5
2004: Bush +2
2008: Obama +4.5
2012: Obama +3
2016: Trump +8.5
Compare Texas:
1992: Bush +3.5
1996: Dole +5
2000: Bush +21.5
2004: Bush +23
2008: McCain +12
2012: Romney +16
2016: Trump +9
Ohio's been arguably trending more Republican, while Texas has been trending more Democratic. I think that O'Rourke has a very good shot at taking out Cruz, and whoever wins the Democratic Presidential nomination in 2020 also has a damn good shot at flipping the state. (If you flip only Texas from Trump to Clinton in 2016, and assuming every elector votes for their party's candidate, Clinton wins the electoral vote 270-268.) Making Texas a swing state would be a huge shift in Presidential politics, and the 2018 races will be very telling as to whether that could happen. Plus, shifting some of the GOP's 25 House seats to the Democrats would be big, and flipping the Governor's office would allow the Dems to get more favourable legislative maps after the 2020 Census.
Texas is definitely a state to watch.