Five-time Grammy award-winning singer Alicia Keys was in Jacksonville last night to host a talent showcase benefiting a mentoring organization founded by a former Jacksonville University student. Six finalists competed for more than $1,500 in cash and prizes at the first Youth Talent Showcase sponsored by Frum Tha Ground Up. Keys’ debut album, Songs in A Minor, sold more than10 million copies worldwide. She did not perform at the event. Keys, 22, said she was happy to stay in the background and encourage the amateur vocalists who took the stage. “Events like this are for inspiration for youth and people in general,” she said. “For me, that’s the most important thing to be part of.” The showcase, at Plush nightclub, was the first official fund-raising and promotional event for the Web-based celebrity outreach and mentoring organization started by D.J. Walton.