It's extremely hard to get. My fiancÚ moved from Virginia to Maryland to go to school here. He needed to stay in MD for one year before he could even think about getting in-state tuition. He needed to have a MD driver's license; his car had to be registered in MD, 1 year of a MD owned bank account, MD voter's registration, and affidavits from people to prove he was going to stay in MD, proof that he has paid MD income taxes. He also had to prove that he was independent from his parents because he was over the age of 19. So proof of residency beyond campus I.e. Apartment, etc. He had to prove that he received no public assistant from the state, I.e. Grants, and stuff like that.
You literally have to prove that you are not just trying to get in-state tuition just to lighten the load for finances. They want to make sure that if you are getting in-state tuition you are going to stay in that state for a long time to come.
Soooo, it's really hard to get in-state tuition. I saw that your info says Colorado. So I found a link to Colorado's Higher Education System. This will help you find out all of the requirements, if you think you could qualify. http://highered.colorado.gov/Finance/Residency/student.html