U.S. Olympian Klete Keller admitted he spent nearly an hour in the U.S. Capitol building on January 6th, pleading guilty to felony obstruction of an official proceeding ... and now faces years in prison.
Remember, 39-year-old Keller -- a 2x gold medalist and former teammate of Michael Phelps -- was caught on video inside the halls of the capitol during the raid.
In fact, KK was wearing a Team U.S.A. jacket ... which helped others identify him once the footage was posted online by reporters.