Driving the “Beat Boebert Buggy” around Colorado, Adam Frisch said he has received about 45 thumbs ups and 20 middle fingers. The congressional candidate hopes this ratio will be repeated in November as he challenges U.S. Rep. Lauren Boebert to represent the 3rd District.

“She’s weak and gonna lose,” he said multiple times at a Saturday meet and greet west of Ridgway, taking a sip of beer each time he repeated the phrase. The game drew laughter and cheers from the crowd of more than 50,...