The reason the non binding straw poll was abandoned was because the RNC had ruled that this election cycle states had to allocate delegates on the basis of a straw poll or primary.
I got this from Rush Limbaugh in his first hour Friday.
Apparently Colorado didn’t want Jeb! to be missing out on all those establishment delegate votes.
If you wanted to be a delegate here and get to the convention you had to pass through the Cruz filter.