WATCH: 'Only in America' could Harris-Walz ticket be possible, Harris says during campaign rally

Vice President Kamala Harris made her first campaign appearance with her running mate, Minnesota Gov. Tim Walz on Tuesday hours after selecting him to join her 2024 ticket. Standing side-by-side with Walz during the Philadelphia rally, Harris said that "only in America" could "two middle-class kids" from such different backgrounds vie for the White House together.