Article continues below advertisementDespite efforts to cover up Joe Biden's declining health, his former Chief of Staff Ron Klain revealed Hillary Clinton told him the ex-president wouldn't be a viable candidate "by 2024."Klain spoke with the House Oversight Committee for over five hours on Thursday, July 24, where he was probed by Committee Chairman James Comer about Biden's health during his 2024 campaign. During which, Klain divulged Clinton's comment.