The Colorado Supreme Court issued an opinion on Amendment 54 yesterday, according to this report.

In another blow to restrictions on political giving by business and labor interests, Colorado’s top court Monday rejected a voter-approved measure to bar holders of large, no-bid government contracts from making campaign contributions.

The opinion is here.  I don’t have time to fully review the opinion now, but Citizens United is mentioned throughout and the opinion discusses the permissible scope of pay to play restrictions.