Former President Bill Clinton should have resigned over his affair with a White House intern nearly 20 years ago, a top Democrat has said.
Senator Kirsten Gillibrand was asked if he should have stepped down following allegations of sexual misconduct against Senator Al Franken.
"Yes, I think that is the appropriate response," she told the New York Times.
Mr Clinton was impeached over his affair with Monica Lewinsky, 22, but was acquitted by the Senate.
Ms Gillibrand, who was one of Hillary Clinton's earliest supporters during the 2016 election, made the comments on Thursday hours after Mr Franken, a Minnesota Democrat, was accused of groping and "forcibly" kissing a woman without her consent during an overseas comedy tour in 2006.
"Things have changed today, and I think under those circumstances there should be a very different reaction," she told the newspaper.
"And I think in light of this conversation, we should have a very different conversation about President Trump, and a very different conversation about allegations against him."
A spokesman for Ms Gillibrand later clarified her comments, saying she had meant that if Mr Clinton's actions had occurred in the modern era, it should have compelled him to resign.
Mr Trump has faced multiple accusations of sexual assault after an audio recording of him boasting about grabbing women was released a month before last year's election.
Eleven women have accused Mr Trump of unwanted touching over several decades.
Mr Trump has called the women "horrible, horrible liars" and described their allegations as "pure fiction" and "fake news".
Anthony Zurcher, BBC News, Washington
Democrats in the 1990s rallied behind President Bill Clinton as he was accused of sexual misconduct ranging from an inappropriate relationship with a White House intern to unwanted advances to sexual assault.
The allegations were viewed as part of a conservative effort to undermine a Democratic administration. The battle lines formed accordingly.
Now, decades later - after #MeToo and a growing list of men take their turn in the headlines - Democrats are asking if their party sacrificed their morals for political expediency.
Mr Clinton's defenders may not have been wrong about Republican motivations, but when it comes to allegations of sexual misbehaviour, does that really matter?
The Clintons still cast a long shadow of Democratic politics, which is why all this still matters - and why any re-evaluation could turn ugly fast. The Kirsten Gillibrand firestorm is just the opening salvo.
The dynamic within the party is changing, however. Old justifications seem insufficient in the context of new attitudes. Rising Democratic stars, like Ms Gillibrand, are vying for prominence as the old guard loses power.
Will an explanation of the high stakes at the time be sufficient when the details of political debates recede from memory? A reckoning is at hand.
Philippe Reines, a former aide to Mrs Clinton, criticised Ms Gillibrand as a "hypocrite" on Twitter.
"Over 20 yrs you took the Clintons' endorsements, money, and seat. Hypocrite," he wrote. "Interesting strategy for 2020 primaries. Best of luck."
Congress has taken action to curb sexual misconduct in government in the wake of a national conversation around sexual misconduct and harassment.
Both the Senate and House of Representatives decided to mandate sexual harassment prevention training for all lawmakers and their staff after hearings on the matter.
The allegations against Mr Franken come as Republican US Senate Candidate Roy Moore faces a string of sexual misconduct claims against him from decades earlier.
Ms Gillibrand, who was elected to Congress in 2006 after Mrs Clinton vacated the seat, has pressed for legislation to make it easier to prosecute sexual assaults in the military.
Her remarks make her one of the most prominent Democrats to say Bill Clinton should have stepped down after the scandal.