Pollster and HarrisX CEO Dritan Nesho said on Tuesday that the anti-establishment movement within American politics will be a long-term phenomenon.

"I think Bernie Sanders Bernie SandersOutrage erupts over Breonna Taylor grand jury ruling Dimon: Wealth tax 'almost impossible to do' Grand jury charges no officers in Breonna Taylor death MORE did well for exactly the same reasons that [President] Trump did well. He ran as an outsider candidate. He ran as a candidate that was trying to shake the establishment. That's very appealing to American voters," Nesho told Hill.TV's Joe Concha on "What America's Thinking."

"We saw this for several of the leading candidates, primarily the person that won the presidency. So I think this phenomenon is here to stay. There's definitely a vein of unhappiness within American politics that needs to be addressed, and will take some time to sort out," he continued.

Nesho's comments come as other anti-establishment candidates, such as New York congressional candidate Alexandria Ocasio-Cortez Alexandria Ocasio-CortezWells Fargo CEO issues apology after saying there was a 'limited pool of Black talent' Brand responds to Trump claim protesters throw tuna cans at police: 'Eat em, don't throw em' CNN's Don Lemon: 'Blow up the entire system' remark taken out of context MORE, gain prominence.

Ocasio-Cortez beat longtime Rep. Joe Crowley Joseph (Joe) CrowleyHillicon Valley: Election officials prepare for new Russian interference battle | 'Markeyverse' of online fans helps take down a Kennedy | GOP senators unveil bill to update tech liability protections 'Markeyverse' of online fans helps take down a Kennedy The Hill's Campaign Report: Trump visits Kenosha | Primary day in Massachusetts | GOP eyes Minnesota as a battleground MORE (D-N.Y.) in the state's 14th congressional district's Democratic Primary last month.

However, establishment figures, such as House Minority Leader Nancy Pelosi Nancy PelosiHoyer: House should vote on COVID-19 aid — with or without a bipartisan deal Ruth Bader Ginsburg lies in repose at Supreme Court McCarthy threatens motion to oust Pelosi if she moves forward with impeachment MORE (D-Calif.), have cautioned that Ocasio-Cortez is not representative of the national Democratic Party.

"It's ascendant in that district perhaps," Pelosi said referring to New York's 14th District, where Ocasio-Cortez is running. "But I don't accept any characterization of our party presented by the Republicans. So let me reject that right now."

— Julia Manchester

--This report was updated on July 25 at 8:45 a.m.