Psychedelic drugs like psilocybin, the psychoactive chemical in “magic mushrooms,” are inching closer to mainstream medical and research use — and unofficial final election results out of Denver suggest at least some Americans are ready to embrace legal measures that could eventually pave the way for that kind of study. A measure on a May 7 Denver ballot appears to have made the Colorado city the first in the nation to effectively decriminalize personal possession and consumption of psilocybin mushrooms, which can cause hallucinations and spiritual or emotional experiences. Though city lawm…