Presidential candidates on the campaign trail week of Sept. 25

Democratic presidential candidate Hillary Clinton and Sen. Bernie Sanders, I-Vt. acknowledge the audience at a campaign stop at the University Of New Hampshire in Durham, N.H., Wednesday, Sept. 28, 2016. (AP Photo/Matt Rourke)

Democratic presidential nominee Hillary Clinton reportedly raised questions earlier this year about primary rival Bernie Sanders' so-called "political revolution," telling donors it was a "false promise."

Clinton took jabs at the Vermont senator's call to achieve policies like universal health care and free college tuition by sparking a "political revolution," according to leaked audio of remarks she reportedly made during a Feb. 16 private event in McLean, Virginia.

Contending that it will take more than one or two presidential terms to revolutionize politics, Clinton accused her primary opponent of promoting a "false promise."

"In order to have the revolution, first we have to take back the Senate and get to 60 votes. Then we've got to take back the House and that may require some redistricting in order to get people out of safe Republican seats so they can be competitive again," she reportedly told donors at the fundraiser. "I think we're already in like year six or seven...Those of us who understand this, who have experience, who've worked in it, know that it's a false promise."

The former secretary of state, however, encouraged her supporters to not be the "wet blanket" on the idealism of young voters who came together behind Sanders, according to the leaked audio.

Instead of telling them they "bought into a false promise," Clinton said she is trying to tout her plans as something that can be achieved from day one.

The Democrat further urged backers to be "very understanding" of experiences that have likely shaped the political views of young Sanders supporters.

"Some are new to politics completely: They're children of the Great Recession and they are living in their parents' basement, they feel that they got their education and the jobs that are available to them are not at all what they envisioned for themselves, and they don't see much of a future...That is a mindset that's really affecting their politics," she reportedly said.

"So if you're feeling that you're consigned to being a barista or some other job that doesn't pay a lot and doesn't have much of a ladder of opportunity attached to it, then the idea that maybe, just maybe you could be part of a political revolution is pretty appealing."

According to the Washington Free Beacon, which posted Clinton's reported remarks, audio from the gathering of major campaign supporters was revealed by hackers who accessed a campaign staffer's email account.

Republican presidential nominee Donald Trump, who has sought to appeal to the Vermont senator's supporters, jumped on reports of Clinton's leaked fundraiser remarks, contending that she is "nasty to Sanders supporters behind closed doors."

Crooked H is nasty to Sanders supporters behind closed doors. Owned by Wall St and Politicians, HRC is not with you. https://t.co/WN1lyCDXla — Donald J. Trump (@realDonaldTrump) October 1, 2016

Release of the reportedly hacked audio comes just days after Sanders, who has endorsed Clinton's White house bid, urged voters to support the former first lady during a joint appearance at the University of New Hampshire.

While many rally attendees who backed the Vermont senator in the primary said they have come around to the idea of supporting Clinton in November, some remained firm that they will not get behind the Democratic nominee.