Answer
The winner of the marathon event at the 2020 U.S. Olympic Trials was Galen Rupp. The event took place in Atlanta on February 29, 2020. Rupp, a two-time Olympian and bronze medalist in the 10,000 meters at the 2012 London Olympics, completed the 26.2-mile course in 2 hours, 9 minutes, and 20 seconds, securing his spot on the U.S. Olympic team for the Tokyo Olympics.