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President Trump has already begun targeting several of the 2020 Democratic presidential candidates with insults — but Sen. Kamala Harris (D-Calif.) has remained a surprising exception.

Trump has already mocked Sen. Amy Klobuchar (D-Minn.) for announcing her presidential run in the middle of a blizzard, and he's continued to hammer on the controversy surrounding Sen. Elizabeth Warren's (D-Mass.) claimed Native American heritage. But the president has said very little about Harris aside from an official White House tweet over the summer claiming that the senator was "supporting" MS-13 gang members. In fact, more recently he's even paid Harris what might be considered a compliment.

"I would say the best opening so far would be Kamala Harris," Trump said in an interview with The New York Times, responding to a question about which Democratic candidate might be the toughest challenger in 2020. "Better crowd, better enthusiasm. Some of the others were very flat."

Trump has also so far refrained from bestowing upon Harris one of his signature nicknames. The president's scathing monikers — "Crooked" Hillary Clinton, "'Cryin'" Chuck Schumer, and Warren's "Pocahontas" frequently appear on his Twitter feed. On the last campaign trail, he belittled other Republican nominees as well, dubbing Sen. Marco Rubio "Little Marco" and Jeb Bush "Low Energy Jeb."

Nothing for Harris, though. As former New Jersey governor Chris Christie recently explained, "If he respects you, you don't get a nickname, because he's afraid what's going to come back", before pointing out that House Speaker Nancy Pelosi (D-Calif.) similarly has no epithet. For now, at least, it seems that Harris is in that same league.