Ms Pelosi, who was instrumental in ousting Mr Biden as the Democratic nominee, has also come in for her share of blame for Donald Trump’s victory.
The US president stepped aside in mid-July, following three weeks of pressure from senior Democrats after his disastrous debate performance against Mr Trump.
He swiftly endorsed Ms Harris, the vice-president, as his successor, prompting the rest of his party to fall in line.
There was speculation that Gavin Newsom, the California governor, or Gretchen Whitmer, the Michigan governor, could make a bid to replace Mr Biden, but neither ended up fighting Ms Harris for the nomination.
‘Own the outcome and fallout’
John Fetterman, the Pennsylvania senator who opposed moves to force Mr Biden out of the race, urged the Democrats who ended his campaign to accept responsibility for the election defeat.
“For those that decided and moved to break Biden, and then you got the election that you wanted, it’s appropriate to own the outcome and fallout,” he told Semafor.
“The options: Double down on the only person that’s ever beat Trump, or demand an alternative. When the outcome didn’t support your thesis and actions, then own it.”
He also appeared to suggest that Ms Harris harmed her election chances when she “pandered” to Left-wing Democrats while running for the presidential nomination in 2020.
The vice-president had supported prisoners having access to taxpayer-funded sex changes, said she was in favour of banning fracking, and mulled the idea of abolishing the immigration agency.
“If someone ran for president in 2020 and pandered to that Squad mentality, or to get likes on Twitter, and they made those kinds of statements about gender, they were going to be pretty hard to defend,” Mr Fetterman said.
Tim Walz, Ms Harris’s running mate, said on Friday that it was “hard to understand” why so many people had voted for Mr Trump.
However, he pushed back against suggestions that Mr Trump’s supporters had voted out of “cruelty or fear or self-interest” and urged Democrats to “swallow a little bit of pride and find common ground” with them.