Jason Kelce is sticking with his underdog brand as his post-NFL career takes off.Tim Nwachukwu/Getty Images Amy Lavin, Temple University and Sheri Lambert, Temple University Philly icon and former Eagles star Jason Kelce has continued to make headlines since he announced his retirement from the NFL on March 4, 2024. A few days after Kelce’s announcement, Campbell Soup unveiled its first Legend Edition Chunky can that pays homage to the former football center. One month later, Kelce surprised fans when he got in the ring at WWE’s WrestleMania XL, which was held in Philadelphia. And on April 29,…