Mark "Vinnie" Dombroski (born December 4, 1962) is an American musician, best known as the lead vocalist and main songwriter for the American rock band Sponge. He also fronted the short-lived supergroup Spys4Darwin, and has been a member of several Detroit-based bands throughout his career. Dombroski is also the lead vocalist and co-founder of The Lucid alongside bassist David Ellefson (ex Megadeth), guitarist Drew Fortier (ex Bang Tango), and drummer Mike Heller (Fear Factory, Raven).