Author and columnist Mark Steyn said Monday that Democratic 2020 hopefuls are moving so far left that they're appearing to run for office as Vermont Sen. Bernie Sanders.

Among the growing field of Democrats looking to unseat President Trump are California Sen. Kamala Harris, New York Sen. Kirsten Gillibrand and former Housing and Urban Development Secretary Julian Castro.

While Sanders (I) has yet to announce a 2020 bid, he has said that he was still "assessing" his plans.

"Everyone is running as Bernie," Steyn said on Tucker Carlson Tonight. "This is a party that is actually moving left at an astonishing rate."

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Steyn pointed out Harris' Medicare for All plan, which she declared is "a fundamental right."

"Everyone is Bernie and there's no room for a Hillary," he said.

Carlson then asked if Sanders himself could succeed "in a field full of lookalikes," which Steyn said poses an interesting question.

He probed whether Sanders could "get away" with pushing socialist policies because of his age.

"[Or] when you actually hang [socialism] around someone in the relative bloom of youth like Kamala Harris, whether that doesn't make the full horror of the unaffordable lavishness of the program seem more evident," he said.

Watch the discussion above.

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