“Billionaire Oprah lectures the rest of us,” he wrote in the tweet, before quoting Winfrey’s remarks, in which she said white people have an advantage on the “ladder of success” because of the colour of their skin.
“What utter, racist BS,” he added.
Mr Cruz was referring to comments Winfrey made in a recent episode of The Oprah Conversation.
Winfrey and former NFL linebacker and activist Emmanuel Acho, who hosts the Uncomfortable Conversations with a Black Man YouTube channel, had been speaking to several white guests about racism.
When one of the guests suggested that not all white people had power and money, Winfrey responded: “You still have your whiteness. That’s what the term ‘white privilege’ is.
“It means that whiteness still gives you an advantage, no matter”.
Winfrey, who has been dubbed the queen of talk show TV due to the success of her hugely popular Oprah Winfrey Show, has a net worth of $2.6 billion (£1.9bn) according to Forbes.
This has led some people, many of them Republicans and right-leaning pundits, to accuse her of hypocrisy.
“And now why is Oprah, maybe the richest black woman in the world, trying to shame white people as privileged? Miss Winfrey, you are the personification of WHITE PRIVILEGE!,” said Irene Armendariz-Jackson, a Republican congressional candidate from Texas.
And Conservative media pundit Todd Starnes said: “I pray for the day that America becomes a nation where someone like Oprah will be able to become a billionaire.”
The Oprah Conversation debuted on Apple TV+ late last month.
The show is “a new series that will continue to explore impactful and relevant topics with fascinating thought leaders from all over the world,” AppleTV+ said in a statement.
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