Cruz has big momentum, he has lost 8 of the last 10
There is something to this view that Trump knew he wouldn’t win CO and allowed this to happen for PR purposes has some truth.
You can say the same thing about MT and SD. I think there are certain states Trump basically conceded. I DON’T think Oklahoma or Wisconsin were two of them, but many others? No, he hasn’t even made an effort there because the numbers don’t work out.
Whether he thought he would make a big PR splash (”cheatin’ Cruz”), well, who knows?
However, I DO think that this plays to Trump. There are many people who know the system is rigged, and by aligning with the rigged establishment, Cruz makes himself less popular.