As more Democrats enter the 2020 presidential race, former chairman of the DNC and former Pennsylvania Gov. Ed Rendell is warning that far-left candidates will only provide fodder for President Trump.

On "Outnumbered Overtime" Monday, host Harris Faulkner asked Rendell who he sees as the current front-runner in the Democratic field, to which he responded, "No one."

He said Sen. Kamala Harris (D-Calif) had the most impressive campaign roll-out, but he said roll-outs are "overrated" when the primary race really heats up later this year.

"The first vote is almost a year away, so I don't think the roll-outs are important at all," Rendell said.

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He added that many of the potential Democratic "heavyweights" -- such as Sen. Bernie Sanders (I-Vt.), former Vice President Joe Biden and former New York City Mayor Michael Bloomberg -- haven't officially entered the fray.

He said that many of the Democratic hopefuls could defeat Trump in the general election, but only if they don't paint themselves into a corner with far-left rhetoric during the primary.

"They're going down the road to socialism," Rendell warned, noting that Trump was "crushed" in the 2018 midterms when the vote was all about him and his administration.

"He's got to make the issue about our candidate, so our candidate can't during the primary season take positions that will give Donald Trump fodder," the former Philadelphia mayor said.

Watch the "Outnumbered Overtime" interview above.

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