“There was a little girl in California who was part of the second class to integrate her public schools, and she was bused to school every day, and that little girl was me,” Harris said. She called his comments about working with segregationist senators “hurtful.”

In a tweet, Democratic presidential candidate John Delaney called Harris’ criticism of Biden an “incredible moment.”

Lynn Vavreck, a professor of American politics and public policy at UCLA, called the moment “among the more amazing things I have seen in a political debate.” She added that Harris “had an amazing night.”

It’s too early to tell how the moment will affect Harris in scientific polls. Still, searches on Google for “busing” spiked more than 3,000% after the senator brought up the issue, according to Google Trends. At one point during the debate, Harris was the top trending topic on Google across the U.S.

Biden, for his part, said Harris mischaracterized his record on race. He said he worked as a public defender instead of a prosecutor, which Harris was as attorney general of San Francisco and California.