Joe Biden has chosen Kamala Harris to become the 2020 Democratic vice presidential nominee.

Biden, himself a former vice president, picked the California senator, elected in 2016, after an extensive vetting process, one that he was surprisingly candid about compared to previous nominees-in-waiting.

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Harris, 55, was a former California attorney general, San Francisco district attorney, and Alameda County line prosecutor before she launched her own White House campaign in January 2019 to comparisons with former President Barack Obama.

Born to a Jamaican father and Indian mother, Harris surged in polling and fundraising following the opening primary debates in June after she confronted Biden for touting his work with segregationists during his 36-year Senate career representing Delaware, and for opposing federally mandated busing in the 1960s and 1970s. But she failed to capitalize on that momentum last summer.

Their fiery debate exchange led to doubts she’d become his running mate, but the pair repaired their frayed relationship.

“I’m so lucky to have you as part of this, this partnership going forward,” Biden told Harris at an April fundraiser. “We can make a great deal of difference, and the biggest thing we can do is make Donald Trump a one-term president.”

He added, “So, I’m coming for you, kid.”

Biden’s selection of Harris as his understudy comes after the civil unrest provoked by George Floyd’s death under the knee of a white police officer. The treatment of Floyd, a black man, amplified calls for a minority woman to be on November’s ticket.

Harris will likely encounter the same challenges ahead of the general election as she did during the primary before she dropped out in December. While the Senate Judiciary and Intelligence committees member rose to national prominence for her incisive questioning of then-Supreme Court nominee Brett Kavanaugh, her bid was hindered by inconsistent performances on the campaign trail. She also struggled to counter criticism regarding contradictions in her prosecutorial record and positions on policies, such as “Medicare for all.”

Biden, 77, was repeatedly pressed by the media and voters alike on the qualities he was looking for in a second-in-command, given his age. He reportedly told allies he’d only be a one-term president as well. In response, he’d say he was searching for someone who was “simpatico” with him on issues and ready to lead at a moment’s notice.