http://www.washingtontimes.com/news/2013/aug/19/colorado-counties-vote-forming-new-state/
Their main complaint is that their vote doesn't count, effectively, because the down state counties are more populous. This is laughable.
Although, I can understand if they are considered about disproportionate representation, as compared to being drowned out. I mean in the US House of Representatives, which is supposed to be a proportionate body, 52% of the people voting for a representative in the last election voted for the political party which represents 47% of the House, while 48% voted for the party that represents 53% of the House. We can't seem to understand proportionality at the national level.