It just makes sense to have four years of President Trump, after which Cruz would be the most likely person to follow. Why? Trump's the only one with the bluster to turn things around quickly enough to have a chance at saving the US.
Cruz is brilliant. He would NEVER EVER take VP position to babysit whiny baby and RUIN his career.
Trumpees like to think this. Maybe they will switch to Jeb or Rubio when Mr. Cruz takes trump out.