© The Hill Reid warns Democrats not to underestimate Trump

Former Senate Majority Leader Harry Reid (D-Nev.) is warning Democrats not to underestimate President Trump in 2020.

"I used to think that Donald Trump was not too smart. I certainly don't believe that anymore," Reid told CNN's David Axelrod during an interview on "The Axe Files" aired late Saturday.

"I don't think he's intellectually a powerhouse, but he is basically a very, very smart man," he added. "No matter what the subject, any argument he involves himself in, it's on his terms. You're always arguing against him. He never, never willing to debate an issue on terms that aren't his."

When asked what advice he would give to a candidate running against Trump, Reid responded: "Well, what I say initially and I say it right here in your show, anyone that thinks Trump's going to be beaten easily should have another think coming."

On #AxeFiles airing Saturday on @CNN, former @SenatorReid warns Dems about @realDonaldTrump & 2020: "I used to think that Donald Trump was not too smart. I certainly don't believe that anymore. No matter what the subject, any argument he involves himself in, it's on his terms. pic.twitter.com/y9seGhuAHV - David Axelrod (@davidaxelrod) October 11, 2019

Reid also weighed in on the Ukraine scandal that's sparked an impeachment inquiry against Trump, saying the president's actions can't go "unpunished."

Reid said the "evidence is very clear" that Trump was withholding aid to Ukraine to pressure its president to investigate 2020 presidential candidate Joe Biden and his son.

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After Axelrod noted there is "almost zero chance" Trump would be convicted in the upper chamber, Reid also said he is disappointed with what the Senate has become.

"I'm also tremendously disappointed in what the Republican senators have not become. They have not become the Mark Hatfields of the world, the John Chafees, the John Hines who are Republican senators who did what they thought was the right thing to do," he said.

"And we have these Republicans who are afraid to speak out against things that he does that are absolutely wrong and they know they're wrong. The only person we've gotten to say anything is Mitt Romney and [Ben] Sasse who said something out of Nebraska. Other than that, they don't say anything."