This is an exaggeration... but I guess one's definition of success is subjective. But I mean, he is well known to "the scene" but never had any real mainstream success. Honestly, it wouldn't be a huge stretch to see him on The Voice considering they have had some known artists on (some who had already been on major labels). I doubt it would ever happen though.
He's on XM Radio all the time and widely known on my college campus, he may not be mainstream in the traditional sense but he sells out venues like 9:30 and TLA using his own name and not even using the Jack's moniker (not to mention People & Things debuted in the Billboard top 10 the week it was released) - making him substantially more recognized than anyone who's come off the voice that wasn't already riding the coattails of Warped Tour notoriety.