The backing of Harris, a black U.S. senator and former 2020 presidential candidate who clashed with Biden during the party’s early debates, could give him a boost as he and Sanders battle for voters before the next round of nominating contests in six states on Tuesday.

Biden, the Democratic front-runner, campaigned in Mississippi, and the more liberal Sanders was in Michigan, both seeking the party’s nomination to challenge Republican President Donald Trump in November’s election.

Below is a summary of Sunday’s events.

FROM ATTACKER TO BACKER

Harris, who has taken Biden to task over his civil rights record, planned to campaign with him on Monday in Detroit, which has a large African-American population.

“There is no one better prepared than Joe to steer our nation through these turbulent times, and restore truth, honor, and decency to the Oval Office,” said Harris, a first-term senator from California and the state’s former attorney general.

One of the most talked-about moments of Harris’ campaign was her blistering attack on Biden during a June presidential debate. She called his remarks about working with segregationist senators hurtful and questioned Biden’s 1970s opposition to school busing.

Still, black voters have backed Biden overwhelmingly, propelling him to big victories in South Carolina’s Feb. 29 presidential primary and on Super Tuesday last week. They will be crucial in Michigan, where they make up almost 14% of the population and as much as 80% of some areas of Detroit.

A number of Harris backers switched their support to Biden after she dropped out of the race in December. She had struggled to build support and raise money. Read more

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