Voters in five Colorado counties said on Tuesday they want to form their own state.  But the breakaway regions face almost impossible constitutional and political obstacles. The North Colorado movement supporters claim that their counties have little in common with more urbanized parts of the state, and they are unhappy with state-wide laws about gun control and energy standards. 

Seth Dixon‘s insight:

There are other secessionist movements, and other ways the states might have formed, but these are all very unlikely.  There’s that little document called the Constitution that makes these movements impractical.  

See on blog.constitutioncenter.org