WATCH: Harris’ ‘heart is her superpower,’ California Sen. Butler says

Sen. Laphonza Butler, D-Calif., has known Vice President Kamala Harris since she first ran for attorney general of California in 2010. In an interview with PBS News on the final night of the Democratic National Convention in Chicago, Butler says Harris is "the exact same person" today as she was back then.

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"Her heart is her superpower," said Butler, who recounted the time Harris as attorney general walked a day "in the shoes of a home care worker" taking care of the elderly and those with disabilities in the Oakland community. "From that moment to this, the same heart has been on display."

Before becoming a senator, Butler worked in advocacy for reproductive rights. She emphasized the importance of building coalitions of voters across the political spectrum in the fight for reproductive rights after the Supreme Court overturned Roe v. Wade.

"We've got to make sure that we're communicating the difference between candidates who stand with voters who support protecting these rights and those who don't," she said.