Keep in mind that while we try to poo-poo the efforts of the Democrats, Colorado used to be a pretty conservative state. However, after the influx of hippies in the '60's, things have turned around. They did enact firearms related legislation, specifically the 10 round magazine one. While it may come about that this is much ado about nothing, I'm inclined to remember that "progressives" believe that the way to achieve their aims is to "progressively" change laws when they can to reach their goal.
As for the Supreme Court, even after the Heller case, the MacDonald case was also needed, but so far as I know, SCOTUS has NOT given carte blanche to gun owners. Automatic weapons are highly controlled and they are working on semi-automatics as we discuss this.
In as much as I like the last two or three justices added to SCOTUS, I still don't have a lot of trust in them.
After all, it was SCOTUS that allowed people to kill their unborn babies.
That's why we need to convince SCOTUS that all of these gun control schemes are unconstitutional. The only way to do that is to convince them that these laws will lead to the deaths of law enforcement and the political class, because they really don't care about the man on the street.