A top aide to Hillary Clinton Hillary Diane Rodham ClintonFox News poll: Biden ahead of Trump in Nevada, Pennsylvania and Ohio Trump, Biden court Black business owners in final election sprint The power of incumbency: How Trump is using the Oval Office to win reelection MORE says the former secretary of State has not ruled out a future bid for president, possibly including a 2020 rematch against President Trump Donald John TrumpSteele Dossier sub-source was subject of FBI counterintelligence probe Pelosi slams Trump executive order on pre-existing conditions: It 'isn't worth the paper it's signed on' Trump 'no longer angry' at Romney because of Supreme Court stance MORE.

Philippe Reines, who served as a senior adviser to Clinton at the State Department, tells Politico in an interview that he thinks it is "unlikely" that Clinton would mount a 2020 bid, but cautioned that it was not an impossibility.

“It’s somewhere between highly unlikely and zero,” he tells in the interview, “but it’s not zero.”

ADVERTISEMENT

Reines goes on to argue that Clinton remains a viable 2020 candidate due to her support base, pointing to the tens of millions of people who voted for her in the 2016 presidential election. Her support, he argues, remains higher than other potential Democratic contenders including Sens. Bernie Sanders Bernie SandersThe Hill's Campaign Report: Trump faces backlash after not committing to peaceful transition of power Bernie Sanders: 'This is an election between Donald Trump and democracy' The Hill's 12:30 Report: Trump stokes fears over November election outcome MORE (I-Vt.) and Elizabeth Warren Elizabeth WarrenHillicon Valley: Subpoenas for Facebook, Google and Twitter on the cards | Wray rebuffs mail-in voting conspiracies | Reps. raise mass surveillance concerns On The Money: Anxious Democrats push for vote on COVID-19 aid | Pelosi, Mnuchin ready to restart talks | Weekly jobless claims increase | Senate treads close to shutdown deadline Democratic senators ask inspector general to investigate IRS use of location tracking service MORE (D-Mass.).

“Chalking the loss up to her being a failed candidate is an oversimplification,” he tells Politico. “She is smarter than most, tougher than most, she could raise money easier than most, and it was an absolute fight to the death.”

“There’s no one in the Democratic Party who has anywhere near a base of 32 million people. That’s multiples of what a Sanders or a Warren have," Reines adds.

Sanders and Warren have both been floated as leaders who could unite the warring wings of the party ahead of a possible 2020 challenge, and both senators have been reportedly making strategic moves in recent weeks that could be seen as preparation for a future bid.

A recent poll of Democrats' views of top 2020 contenders showed Sanders in second place, ahead of Warren but trailing former Vice President Joe Biden Joe BidenPelosi slams Trump executive order on pre-existing conditions: It 'isn't worth the paper it's signed on' Hillicon Valley: Subpoenas for Facebook, Google and Twitter on the cards | Wray rebuffs mail-in voting conspiracies | Reps. raise mass surveillance concerns Fox News poll: Biden ahead of Trump in Nevada, Pennsylvania and Ohio MORE. Clinton, who defeated Sanders in the 2016 Democratic primary and won the popular vote in the general election, was not listed on the poll.

A former Clinton campaign strategist threw cold water on the likelihood of a 2020 bid for president from the former first lady earlier this year, calling the prospect a "pipe dream" in an interview with Hill TV.