I'm just now starting to look into this, but apparently from documents both here on OCDO and other sources, Colorado's preemption of firearms has suffered a judicial defeat that has rendered it useless.
From
http://www.opencarry.org/co.html, we have:
"Colorado was once one of our "Gold Star" open carry states. However, Denver filed and won a suit challenging the states excellent preemption law. Consequently, both open carry and unlicensed open car carry in Denver are prohibited. There are reports that other localities are planning to follow suit."
From
http://www.coloradoceasefire.org/munilaws.htm, we have:
"Concealed Carry Bans: Aurora, Boulder, Broomfield, Colorado Springs, Denver, Englewood, Lakewood, Littleton, Longmont, Northglenn, Pueblo, Thornton, Westminster, Wheat Ridge"
I haven't read the details on how they lost the lawsuit, but it would seem to behoove us to learn about it, so we can protect our own preemption law here in Virginia.
TFred