Up-and-Comers: The “Up-and-Comers” category tracks celebrities who may be ready to experience a break out.  It measures the highest appeal  among celebrities with less than 15% total awareness.  Breakout YouTube sensation Jenna Marbles heads this list.  48% of those aware of Marbles say they “Like (her) a lot.” Number two on the “Up-and-Comers” list is Jon Stewart’s summer fill-in, John Oliver.  Also on the list are TV actors Nick Offerman (Parks and Recreation) and Donald Glover (Community).