After a raucous debate eight days ago between Mr Trump and Mr Biden, Mr Pence and Ms Harris took a more civil tone with no name-calling, but sharply disagreed on the reaction to the pandemic.
Ms Harris, the daughter of Jamaican and Indian immigrants, would also be both the first African-American and Asian-American vice president.
At one point, Ms Harris, firmly but with a smile, reproached Mr Pence, telling him: “Mr Vice President, I’m speaking.”
President Trump appeared to be watching the vice presidential debate avidly, tweeting without using Ms Harris’ name that “she is a gaffe machine”.
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