The Skimm co-founders and co-CEOs, Carly Zakin and Danielle Weisberg, have grown their company to more than 6 million newsletter subscribers today. They open up about the initial challenges they faced getting investors on board, why they feel a responsibility to educate their audience, and how they are using their platform to get more millennials to register to vote. Produced by Haley Draznin, CNN.To learn more about how CNN protects listener privacy, visit cnn.com/privacy