NEW YORK, NY - JANUARY 15: Singer Ella Henderson enters the "Late Show With David Letterman" taping at the Ed Sullivan Theater on January 15, 2015 in New York City. (Photo by Ray Tamarra/WireImage)
NEW YORK, NY - JANUARY 15: Singer Ella Henderson enters the "Late Show With David Letterman" taping at the Ed Sullivan Theater on January 15, 2015 in New York City. (Photo by Ray Tamarra/WireImage)