Power 50: Kate Mckinnon

Photo: Chris Pizzello/Invision/AP

Her hilarious impersonations on SaturdayNightLive have turned media-shy McKinnon into a breakout star, and America's newest sweetheart. From Justin Bieber to Ellen DeGeneres to Hillary Clinton, the comic has nailed pop culture impressions to a T, amassing millions of views on the Web. Now she's on her way to becoming a bona fide Hollywood star: Her lead role in this summer's all-female Ghostbusters reboot could cement her A-list status and put her in the same league as Tina Fey, Amy Poehler, and Kristen Wiig.