For years, candidates for mayor in Denver and in other large cities have vowed to end scenes of tents and tarps lining sidewalks and parks, but Mayor Michael Hancock warns that voters should be wary of anyone who claims they can fix the problem in a set amount of time. Hancock, who has dealt with persistent criticism over his handling of homelessness, said he wishes he had understood the issue’s complexity when he was first elected as mayor in 2011. “We have not been sitting around for 10, 11 years twiddling our thumbs and playing politics with the lives of human beings on our streets.