Harris vs. Biden showdown was most-watched Democratic primary debate in history

WASHINGTON – Sen. Kamala Harris sparring with former Vice President Joe Biden apparently made good TV — so much so that Thursday's Democratic debate was the most-watched in history, according to preliminary ratings from Nielsen released by NBC.

The debate, which featured 10 of the 24 candidates seeking the Democratic nomination for president -- including some of the most popular thus far in the race, averaged 18.1 million viewers across NBC, MSNBC and Telemundo, the three networks that aired the two-hour broadcast. It surpassed night one of the debate on Wednesday, which saw 15.3 million viewers.

Thursday's viewership surpassed the previous highest-rated Democratic primary debate in 2015 by 2.6 million viewers, according to NBC.

More: Second Democratic debate sets record with 18 million viewers (thanks, Kamala Harris)

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But, none of the debates came close to the Republican primary debates. President Donald Trump's appearance on the debate stage on Fox News in 2015 averaged a whopping 24 million viewers. One month later, 23 million tuned in to a Republican debate on CNN.

Thursday's debate saw some of the most talked-about moments in the 2020 race thus far.

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Harris challenged Biden over his remarks last week about working with segregationist senators James Eastland and Herman Talmadge. Turning to Biden on Thursday, Harris said she doesn’t think he’s racist, but she said it’s “hurtful” to hear him talk about finding common ground with who two senators who built their reputation and career on segregation.

Harris cited Biden’s fight against school busing and told the story of a young California girl who was part of the second class to integrate her school.

“That little girl is me,” she said.

Biden watched stone-faced as Harris attacked him. When he got his chance to speak, he fired back at Harris, calling her criticism a “mischaracterization.”

Speaking Friday at Rev. Jesse Jackson's Rainbow Push Coalition's annual convention, Biden addressed the issue again. "We all know that 30 to 60 seconds on a campaign debate exchange can't do justice to a lifetime committed to civil rights," Biden said. "I want to be absolutely clear on my record and history on racial justice, including busing. I never, never, never ever opposed voluntary busing."

More: After clash with Harris, Biden pushes back on race criticism

Thursday's debate was filled with candidates talking over one another, ideas on how to change the country and attacks aimed at the current occupant of the White House.

Along with Biden and Harris, the debate featured Sen. Bernie Sanders, Mayor Pete Buttigieg, Sen. Michael Bennet, author Marianne Williamson, Rep. Eric Swalwell, Sen. Kirsten Gillibrand, entrepreneur Andrew Yang and Gov. John Hickenlooper.

Contributing: Aamer Madhani, USA TODAY; Bill Goodykoontz, Arizona Republic

This article originally appeared on USA TODAY: Harris vs. Biden showdown was most-watched Democratic primary debate in history