WASHINGTON – Many of the two dozen candidates seeking the 2020 nomination this weekend denounced social media comments questioning Sen. Kamala Harris's identity as an African American.

But Harris was not the only African American Democratic candidate whose black identity was questioned last week.

Replaying a segment in which some candidates used Spanish on the first night of the Democratic debate in Miami, Fox News host Tucker Carlson on Thursday referred to New Jersey Sen. Cory Booker, who is black, as one of the "whitest" Democrats running for president.

Carlson made the remark about Booker after showing a clip of New York Mayor Bill de Blasio calling for higher taxes on the wealthy during the debate, which Carlson interpreted as Democrats saying, "We're coming for your stuff."

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"That was the major theme of last night," Carlson said Thursday. "And, in case anyone missed it, the two whitest candidates on stage decided to repeat the point in stilted Spanish."

Carlson then cut a clip of former Texas Rep. Beto O'Rourke answering a question about tax policy in Spanish. He then showed Booker saying in Spanish, "This president has attacked, has demonized immigrants. It's unacceptable."

"Got that, gringo?" said a chuckling Carlson. "You can add the English language to the long and growing list of things the Democratic Party considers racist. How long before you're banned from speaking it? Think we're joking? Right. Better to learn español if you want to talk to your grandkids. It's a brand new world."

Booker's campaign declined to comment on Carlson's remarks when contacted by USA TODAY.

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Booker was not the first African American politician whose black identity was questioned by Carlson.

"How is he black, for one thing? He has one white parent, one black parent," Carlson said in an April 2006 discussion about Barack Obama – then a newly elected U.S. senator from Illinois – on a shock-jock radio program called "Bubba the Love Sponge"

"Why isn't he white?" Carlson asked in the interview, which was published online by the liberal site MediaMatters.

In a 2008 interview, "The Love Sponge" told Carlson that Obama would "kick your ass playing basketball."

"Yeah, of course he would. Basketball? Come on," Carlson said. "I don't know how black he is, but I'm sure he's a good basketball player."

Carlson has been a target of leftist critics and last year Antifa protesters arrived at his house, breaking his door when his wife was home alone.

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