Mock-up of a mobile billboard tying Colorado Democratic Senate candidate Andrew Romanoff to U.S. Rep. Alexandrai Ocasio-Cortez, D-New York, sponsored by the National Republican Senatorial Committee. The billboard will appear on the University of Colorado Boulder campus on Saurday, ept. 21, 2019, to coincide with a county Democratic Party dinner featuring the popular progressive congresswoman, who is known as AOC.