On Tuesday, Biden said in an email to supporters, "I’ve decided that Kamala Harris is the best person to help me take this fight to Donald Trump and Mike Pence and then to lead this nation starting in January 2021."
"I need someone who understands the pain that so many people in our nation are suffering. Whether they’ve lost their job, their business, a loved one to this virus. This president says he “doesn’t want to be distracted by it”. He doesn’t understand that taking care of the people of this nation -- all the people -- isn’t a distraction -- it’s the job. Kamala understands that," the 77-year-old candidate continued.
Harris tweeted, "@JoeBiden can unify the American people because he's spent his life fighting for us. And as president, he'll build an America that lives up to our ideals. I'm honored to join him as our party's nominee for Vice President, and do what it takes to make him our Commander-in-Chief."
Biden's selection marks just the third time in history a woman has been chosen as a running mate on a major party presidential ticket and the first time a Black and South Asian woman is elevated to the role.
Celebrities flocked to Twitter to congratulate Harris and show their support for the 2020 ticket.
"Very happy for our friend and Senator and future Vice-President, @KamalaHarris, and very much looking forward to voting for the Biden-Harris ticket to begin the difficult work of recovering from this nightmare presidency and building an even better future," said John Legend.
Wife Chrissy Teigen said she's "excited to vote" in 2020 after the announcement was made.
Patton Oswalt joked, "Not cool, Joe. You know Pence can't be alone onstage to debate Harris. Why put that poor, frail flower through all this angst?"
While Mindy Kaling just posted emojis.
Sharon Stone wrote, "Congratulations @KamalaHarris. I am thrilled for you and relieved and excited for our country. God Bless America! PS I knew it would be you, because @JoeBiden respects those who confront him with dignity. Bravo! To both of you!"
Rob Reiner said, "Finally a Presidential ticket that looks like America!! Now we all go to work to restore the soul of our Nation. VOTE!!!!"
Whoopi Goldberg said, "Sen.KamalaHarris this is a great moment. Let’s take care of her and make sure we are supportive of her because this is a no nonsense race and she is ready. Go Kamala!!"
Rosie O'Donnell tweeted a photo of Harris and Biden with the caption: "AMEN!!"
"This is great news!! I can tell you from personal experience that @KamalaHarris is one incredible person. Tough and with a huge heart. She would make the perfect VP! And herstory as the first woman. Excited for our upcoming interview on @thedailypopcast!" said Lance Bass.
Meanwhile, Maya Rudolph, who has done impressions of Harris on "Saturday Night Live," told Entertainment Weekly on Tuesday: "Oh s--t, ruh-roh," shortly after Biden announced his pick.
In choosing Harris, Biden is embracing a former rival from the Democratic primary who is familiar with the unique rigor of a national campaign. Harris, a 55-year-old first-term senator, is also one of the party’s most prominent figures and quickly became a top contender for the No. 2 spot after her own White House campaign ended.
Next week, both will speak at the Democratic National Convention (Mon, Aug 17, 2020 – Thu, Aug 20, 2020) which is going virtual since the COVID-19 pandemic led party officials to cancel all in-person plans in Milwaukee.
Speakers on the list to offer their words of support range from progressive Rep. Alexandria Ocasio-Cortez to Republican John Kasich, a former Ohio governor who sought the GOP presidential nomination four years ago.
Biden's former opponents Sen. Bernie Sanders, Sen. Elizabeth Warren, Sen. Cory Booker, and Mayor Pete Buttigieg will speak as well.
And, of course, former Presidents Barack Obama and Bill Clinton, and former first ladies Michelle Obama and Hillary Clinton, along with Biden's wife, Dr. Jill Biden will take the stage.
Programming is set to be broadcast and streamed online each night from 9 p.m. to 11 p.m. EDT.
The Associated Press contributed to this report.