In the run up to the 2020 Presidential Election, then-Senator Kamala Harris announced her candidacy for the Democratic Party's presidential nomination on January 21, 2019. At that time she had been a United States Senator from California for only two years, but had spent six years as Attorney-General for the state of California. and before that as District Attorney of San Francisco for seven years. She participated in a number of all-candidates debates for the party, in which she was criticized by her opponents for her record as the state Attorney-General. The criticisms were primarily about her past positions on prosecuting marijuana users, calling for cash bail from those who could not afford it, her parole reforms, and alleged negligence in investigating police misconduct. Her campaign faced challenges with poor poll numbers and weak fundraising, as well as complaints from staff. She officially withdrew from the Democratic primaries in December of 2019 and went on to endorse Joe Biden on March 8, 2020, despite having attacked him during a debate over Biden's position on bussing when he had been a Senator. Biden let go of any hard feelings he had over the attack and selected Harris to be his running mate on August 11, 2020. After Biden and Harris won the general election, she became the first female vice president of the United States on January 20, 2021.
In October 2023, Harris was asked about what would happen if President Biden was to drop out of the race for President and as expected she refused to answer the question. After the first presidential debate on June 27, 2024, significant concerns grew about Biden's age and fitness to serve a second term. At first Biden pushed back "aggressively" at the idea that he should drop out.
After the debate, an old clip of Harris was posted on social media in which she asked her audience: "You think you just fell out of a coconut tree? You exist in the context of all in which you live and what came before you." This video became a popular internet meme and coconuts soon became a symbol of Harris's campaign.
By July 3, Harris was being discussed as Biden's potential replacement by senior Democrats. The suggestion was not universally welcomed. In the meantime Harris defended Biden, saying that the debate "wasn't his finest hour" but that "the outcome of this election cannot be determined by one day in June." But for many, the die appeared to be cast. Harris was a frequent target of speeches during the 2024 Republican National Convention held from July 15 to 18, even though she was not yet a candidate for President. On July 17, the Trump campaign refused to select a date for a vice presidential debate because they said that it was unclear who the Democrats' vice presidential nominee would be if Biden were to withdraw.
On July 18, The Hill reported that in the next few days, Biden would make a speech about the future of his political career, and that congressional Democrats expected Harris to be the new nominee.
Other candidates such as Governors Gavin Newsome of California, Gretchen Whitmer of Michigan and Josh Shapiro of Pennsylvania.
Pressure began to mount with more and more prominent Democrats and celebrities calling for Biden to withdraw as a candidate for President. Democratic Party fundraising also began to stall. Finally on July 21, 2024, and Biden withdrew as the Democratic Party's nominee for President and endorsed Harris as his successor.
Later that day, on July 21, 2024, Harris announced her intention to run as a candidate for the Democratic Party's presidential nomination. The "Biden for President" campaign committee filed paperwork with the Federal Election Commission to change the name of the committee to "Harris for President".
On July 22, Harris received enough state delegate endorsements to win the nomination and become the presumptive nominee.
These endorsements were non-binding, but they were sufficient in number for her to secure enough delegates to win the nomination.
The day Biden's withdrawal was announced, Democratic fundraising platform ActBlue reported raising more than $50 million. In the first 24 hours of Harris's candidacy, the presidential campaign raised $81 million in small-dollar donations, the highest single-day total of any presidential candidate in history. By August 1, ten days after the launch of the campaign, the Harris campaign raised $310 million in small-dollar donations through ActBlue.
Harris held her first campaign rally on July 23, 2024, at the West Allis Central High School gymnasium in West Allis, Wisconsin. The event reportedly grew a larger audience than any event held by Biden's 2024 campaign. A week later on July 30, Harris held an event in Atlanta at the convocation center of Georgia State University. In her speech she told the crowd
of 8,000 people, "Well Donald, meet me on the debate stage. If you've got something to say, say it to my face." Pop music artis Megan Thee Stallion performed several songs and addressed the subject of reproductive rights. The rapper Quavo also performed and spoke about the work he and Harris had done n the field of gun violence prevention.