Jon Huntsman is finishing up as Obama's ambassador to China, but his supporters are already crafting his "hip" persona—his motorcycle, cover band, youthful indiscretions. McKay Coppins on whether it'll be enough in 2012 to win Huntsman crucial under-40 voters, who swarmed to Obama in 2008.If you've been following the political news over the past few weeks, these are the things you've learned about Jon Huntsman Jr., outgoing ambassador to China:He drives a motorcycle.He once played in an REO Speedwagon cover band.He briefly dropped out of high school, where he hung out with kids who were "very active in drugs"...