Colleen Long, Zeke Miller, Steve Karnowski, Will Weissert and Seung Min Kim | Associated Press

The vice president and Democratic presidential candidate says Walz is the "kind of person who makes people feel like they belong and then inspires them to dream big." For his part, Walz revved up the crowd in Philadelphia for the rigorous campaign to come, saying, "We've got 91 days" and "We'll sleep when we're dead."