There was not an open election in Colorado... it was voting performed at the county conventions.
It was decided to be a grassroots effort last August.
http://www.denverpost.com/news/ci_28700919/colorado-republicans-cancel-2016-presidential-caucus-vote
Not a single thing stopped Trump from putting together a team to get the votes needed to win the delegates. But your fearless leader showed the kind of team he could put together... a losing one.
Cruz is corrupt.