Sen. Cory Booker (D-NJ) on Sunday emphatically said his roots “go back to slavery” and his roots rose up during the civil rights struggles in the 1960s, potentially previewing a major potential point of contrast between him and Sen. Kamala Harris (D-CA) as they court the party’s critical black primary voters.

Speaking at the “Bloody Sunday” commemorative service at the Brown Chapel AME (African Methodist Episcopal) Church in Selma, Alabama, Booker told the story about how his “roots rose up in the 1960s” when his parents tried to buy a home in New Jersey. He said they were often “denied housing because of the color of their skin” and even had dogs sicced on them.

“We’ve got to remember we cannot handle the moral amnesia that forgets the roots that are in the soil that was poisoned with hatred and bigotry but still found root in the ground,” Booker said. “We may be the fruits, but we cannot forget the roots. My roots go back to slavery. They rose up through poverty and segregation, hardship and pain. Rose up from black churches, through civil rights organizations, through HBCUs.”

He said a volunteer white housing lawyer and others who were inspired by the voting rights protests in Selma eventually helped his parents buy their home.

“They set up an operation where my parents would go look at a house and be told it was sold, and the white couple would follow them and find out that the house was still for sale,” Booker said. “My parents were told the house was sold. The white couple found the house was for sale. The white couple put a bid in on the house. The bid was accepted. Papers were drawn up. A closing was set. On the day of the closing, the white couple didn’t show up.”

He said after his father and a volunteer lawyer “marched into that real estate agent’s office,” the agent was so angry that they “ran a ruse on him” that “he stands up and punches my dad’s lawyer in the face and he sicced a dog on my dad.”

“My parents told me when I was sitting around my kitchen table, ‘boy, you’ve got to remember the struggles it took to get you here,’” Booker said.

Because South Carolina, the first-in-the-South primary state in which a majority of primary voters are expected to be black Democrats, will likely make or break Booker’s campaign, the issue of African-American identity—and which candidate better understands the experiences of African-American voters in the South–will be intensely discussed in the coming months.

Last month on CNN, host Don Lemon said it is okay for voters to question whether Harris is an “African-American” because “there’s a difference between being African-American and being black.”

Lemon said voters may want to know if Harris, whose mother was from India and father from Jamaica, is “someone who came out of Jim Crow, out of American slavery.”

“No one is saying she is not black. We are asking if she is African-American,” Lemon said. “There is a distinction. There is nothing wrong with asking that question.”

When CNN contributor April Ryan mentioned that “many Africans landed in Jamaica and all these other Caribbean islands,” Lemon said that “Jamaica is not America” and “Jamaica did not come out of Jim Crow.”

“There is nothing wrong with making a distinction to say that you’re a black person who comes out of the American tradition of being black or African-American,” Lemon continued. “What is wrong with that? Absolutely nothing.”

Lemon added that all Harris needs to say is, “I am a black woman, my ancestors are not African-American,” and “then just move on.”

“That’s not a controversy,” he added. “It should not be controversial at all.”

Last month on the “The Breakfast Club” radio program, Harris, addressing questions about her heritage, said she was born in Oakland and raised in the Bay Area except for the years that she went to high school in Montreal, Canada.

“And look, this is the same thing they did to [former President] Barack [Obama]. This is not new to us, and so I think that we know what they are trying to do,” Harris said. “They are trying to do what has been happening over the last two years, which is powerful voices trying to sow hate and division, and so we need to recognize when we’re being played.”

Harris also said she is not going to spend her time “trying to educate people about who black people are.”

“I’m black, and I’m proud of being black. I was born black. I will die black, and I’m not going to make excuses for anybody because they don’t understand,” Harris said.

Lemon’s comments were similar to those that columnist Stanley Crouch made about Barack Obama before he became president.

“His father is a black Kenyan. Other than color, Obama did not – does not – share a heritage with the majority of black Americans, who are descendants of plantation slaves,” Crouch wrote in 2006. “Of course, the idea that one would be a better or a worse representative of black Americans depending upon his or her culture or ethnic group is clearly absurd.”

Crouch added then that if America elects “the son of a white woman and an African immigrant” as “our first black President, he will have come into the White House through a side door – which might, at this point, be the only one that’s open.”