Barack Obama has privately told some allies that president Joe Biden’s debate performance had badly dented his re-election chances, which is much harsher than the former president’s public statements about the campaign. Sources told the Washington Post that Obama had spoken directly with his former vice president by phone after Thursday’s debate, although it’s not clear whether he commented directly on his decrepit appearance onstage and his election chances. “Bad debate nights happen,” Obama posted on social media after the debate. “Trust me, I know. But this election is still a choice betwee…