Obama endorses Harris for president in a whirlwind week of party support

Former President Barack Obama endorsed Vice President Kamala Harris for president Friday, just days after she launched her campaign after President Joe Biden withdrew from the race.

"Michelle and I couldn’t be prouder to endorse you and to do everything we can to get you through this election and into the Oval Office," Obama says in a video that shows Harris getting a call from the Obamas.

Michelle Obama says in the approximately one-minute video: "I can’t have this phone call without saying to my girl Kamala: I am proud of you. This is going to be historic."

Obama, the first Black president, and Harris, who could become the first female president, have been in close touch since she announced her candidacy Sunday, and he has privately been fully supportive, according to four people familiar with their discussions, NBC News has reported.

“He has been in regular contact with her and thinks she’s been off to a great start,” one of them said.

Aides to Obama and Harris have discussed their appearing together on the campaign trail at some point, three of the people familiar with the discussions said.

Obama had supported Biden's re-election effort, but he had "concerns" about Biden’s prospects in November after his weak debate performance in late June.

Moments after he announced he was dropping out of the race Sunday, Biden endorsed Harris for president, and Democrats quickly coalesced around her.

Former President Bill Clinton and former Secretary of State Hillary Clinton also endorsed Harris in a joint statement Sunday.

While Obama praised Biden's leadership as president and his life dedicated to public service in a statement released the day he made his announcement, he didn't endorse Harris then.

Harris' and Obama's political lives have intertwined over the last two decades as they have campaigned with and endorsed each other for various elected offices. When she was San Francisco district attorney, Harris was a co-chair of Obama's California campaign when he ran for president as a senator. During the race, she attended Obama's launch speech in Springfield, Illinois; campaigned for him in Iowa, Nevada, Pennsylvania and New Hampshire; and attended his victory speech in Chicago's Grant Park when he won the general election, the San Francisco Chronicle reported at the time.

Soon after Obama won in 2008, Harris announced she would run for attorney general of California, telling the Chronicle: “To be sure, Obama has excited a whole new generation of voters — and ... they span all ages and categories. But they’re an excited group of people who are feeling good about the country, and they want to be involved in it — and those are the people I want to talk to.”

In 2010, Obama endorsed Harris for attorney general, an office she won and held for six years. And in 2016, he endorsed and cut a TV ad for Harris when she ran for the Senate.

Obama also nominated Harris' brother-in-law, Tony West — another prolific Obama supporter — to be the head of the Justice Department's Civil Division in 2009. He went on to become an associate attorney general at the Justice Department in the Obama administration.

This story first appeared on NBCNews.com. More from NBC News:

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