Is Online Poker Legal in Colorado?
Colorado does offer casino gambling in a few cities across the state. They have not always been as gambling friendly as they are now. A change in laws in 1990 expanding gambling and now the state is one of the better gambling destinations in the US. Though Colorado allows a number of gambling options their laws are rather strict. The law defines gambling as:
The risking of money or other thing of value for gain contingent in whole or in part upon lot, chance, or the happening of an event over which the person taking the risk has no control. 
Casinos and Live Poker
There are casinos in three Colorado cities, which include Central City, Cripple Creek and Black Hawk. In 1990 the state passed a referendum that allowed casino in the three cities. Each of cities had once been a booming gold rush towns, but had since become ran down.
Casinos in these three cities offer live poker rooms. You can find a list of rooms here. Colorado law also allows for social home poker games as well. Other gambling in the state includes dog racing, horse racing, bingo and a state lottery.
There are no laws in the state of Colorado regarding online poker. There has not been a strong movement to either regulate or outlaw online poker in the state. Even though there are no specific laws on online poker or gambling in the state a lower court in Colorado did rule that poker was gambling. The State Supreme Court later decided to decline hearing an appeal of the decision.
Currently there does not seem to be a strong chance to see regulated online poker in Colorado, but the state might be a good fit for future intrastate poker. Poker is popular in the state which has a strong libertarian streak, proof being they were the first state to legalize non-medical marijuana.