US senator Bernie Sanders has offered contrition as some of his 2016 presidential campaign staff face allegations of sexual harassment that threaten to derail a second White House bid before it begins.
Hours after a New York Times report detailed allegations of unwanted sexual advances and pay inequity on his first campaign, Mr Sanders apologised "to any woman who felt that she was not treated appropriately".
"Of course, if I run again, we will do better next time," the Vermont senator told CNN.
Yet there were signs that the allegations, which did not directly involve Mr Sanders, could hurt the self-described democratic socialist's 2020 ambitions in the midst of the #MeToo era.
In the wake of the report, some Democratic activists and operatives complained about the aggressive culture during the first campaign, when male staff and supporters were sometimes labelled "Bernie bros".
"I'm not the least bit surprised," National Organisation for Women president Toni Van Pelt told the Associated Press, noting she was forced to block Mr Sanders's supporters from her social media feed in 2016.
"To me, it was really clear this was the way they were running the campaign."
She blamed Hillary Clinton's loss to Donald Trump, at least in part, on Mr Sanders and his supporters.
"It wasn't just Trump, it wasn't just the Russians, it was also the sexist people that ran his campaign," Ms Van Pelt said.
The timing could not be worse for Mr Sanders, who is gearing up for a second presidential bid.
His senior adviser said last month that Mr Sanders would run a "much bigger" operation and would start out as a front-runner if he ultimately decided to run.
Yet the 2020 Democratic field would have little in common with that of 2016, in which Mr Sanders emerged as the anti-establishment alternative to Mrs Clinton.
Should he run again, the 77-year-old would enter a crowded field that features multiple prominent liberal women.
Massachusetts senator Elizabeth Warren has already launched a presidential exploratory committee.
Senator Kirsten Gillibrand of New York, who has been a central figure in Washington's reckoning with the #MeToo era, is considering a presidential run.
Senator Kamala Harris of California could also be a leading contender.
Even before the Times' story was published, Politico reported that more than two dozen former campaign workers and volunteers had requested a meeting with Mr Sanders to discuss alleged sexual violence and harassment that occurred during the 2016 campaign.
The Times detailed one situation in which a campaign surrogate was said to have touched a strategist's hair in a "sexual way", among other unwanted advances.
It also reported that in some cases, women were expected to sleep in the same quarters as men they did not know.
Others discovered examples of men who were paid significantly more for doing similar jobs.
Mr Sanders's wife, Jane O'Meara Sanders, said the meeting with concerned former staff and volunteers would take place in a matter of days, although it had not yet been scheduled as of late Wednesday.
"The fact is if somebody didn't feel safe in any way, it was a failure. I, we, apologise profusely. This is not acceptable," she said.
"Of course things happen in our society. The question is, 'How do you handle them?'
Ms O'Meara Sanders said she and her husband became aware of the allegations only after the campaign was over.
They subsequently implemented a series of safeguards on his 2018 Senate re-election campaign, which included mandatory staff training, strict guidelines and the creation of a complaint hotline run by a third party.
"We didn't hear specific things during the campaign. We heard some of them after the campaign. We've heard others just now that were never reported," Ms O'Meara Sanders said.
"We were, as you can imagine, out on the road and you do delegate. But we do think at the top level, people did the best they possibly could."
Mr Sanders noted the 2016 campaign grew from just a handful of employees to roughly 1,200 workers in just a few months.
"I am not going to sit here and tell you we did everything right in terms of human resources," he told CNN.
There was no immediate indication that Mr Sanders was backing away from another presidential run.
When asked about her husband's 2020 aspirations, Ms O'Meara Sanders said the new situation would have no impact on their plans.
RoseAnn DeMoro, executive director of the National Nurses United and a chief Sanders ally, suggested the revelations might help his political future by forcing an important conversation and stronger anti-harassment policies.
"This is Bernie Sanders. This is someone who believes from the bottom of his heart in equality. He does. I think he'll be the best president in the history of America on equality," Ms DeMoro said.
"I'm hopefully going to be part of organising every woman in this country for Bernie in 2020."
Nina Turner, who leads the Sanders' political arm, Our Revolution, noted that none of the women who alleged misconduct said Mr Sanders had any direct knowledge.
"This is hurtful, this moment is heavy - as well it should be when people are coming out saying they were mistreated in the campaign based on their gender," Ms Turner said in an interview.
But on the ground in South Carolina, a key state on the presidential primary calendar where Mrs Clinton beat Mr Sanders in 2016, Democratic state senator Marlon Kimpson said people were already decidedly "less enthusiastic" about Mr Sanders heading into 2020.
Mr Kimpson said the state's Democratic primary voters - most are women - would want to hear directly from Mr Sanders about what he knew about the allegations and when.
"In this day and age, the allegations of sexual harassment have to be taken very seriously and action must be taken swiftly to send a message to your campaign that this behaviour will not be tolerated," Mr Kimpson said.
"This will be a material issue in people making up their minds if he's talking the talk and walking the walk."
Ms Van Pelt cast the blame on Mr Sanders whether he had direct knowledge of misconduct or not.
"If he didn't know," she said, "he has no business being in office."