Sugarland, Sheryl Crow and Dave Matthews performed Sunday night (Aug. 24) near Denver during a kick-off concert for the Democratic national convention. The event at Red Rocks Amphitheatre was designed to call attention to environmental issues. During the concert, Sugarland's Jennifer Nettles told the crowd, "I wonder how many of you know who we are and what we do. We are here to support environmental awareness. ... Country music artists are stereotyped in so many ways. You think we don't care about the environment. We do." Nettles and Sugarland partner Kristian Bush have not endorsed a candidate and declined to divulge whether they are Democrats or Republicans. "This show has us here, specifically for this issue," she told Denver's Rocky Mountain News newspaper. "It's the first time in history -- that I've heard about or read about -- that the issue of environmental awareness has been at the forefront ... of a [major political convention] of any sort."