Vowing to "bring our voices together", Harris would be the first woman to hold the presidency if she succeeds.
The 54-year-old is a former prosecutor and California Attorney General - a past that Cal Matters columnist Dan Walters says could both hurt and help her chances.
For the Democratic nomination, Harris is expected to face competition from senators Elizabeth Warren of MA and Kirsten Gillibrand of NY, in addition to potential campaigns from Sherrod Brown of Ohio, Amy Klobuchar of Minnesota, and Corey Booker of New Jersey. The first four candidates to declare are all women.
Harris, who served as California's attorney general before joining the Senate, made her long-anticipated announcement on Monday during an appearance on ABC's 'Good Morning America'. Attorney generals are obliged to uphold and defend state law.
The Californian's pro-immigration positions, including an early refusal to compromise on Trump's border wall, has endeared her to activists prominent in the Latino community.
Still, he says Harris is on solid footing for the primaries, even with a large field of candidates expected. She was the first senator to call on Homeland Security Secretary Kirstjen Nielsen to resign for carrying out Trump's family separation policy for illegal border-crossings.
"Let's do this together", she said.
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He also was injured in the Christmas game and three days later had surgery to fix a ligament in his right ring finger. Walton was impressed with his second-year point guard's overall effort, especially late in the game.
Harris chose to announce on Monday to honor the legacies of two of her heroes. In a bid to introduce herself, she launched a requisite campaign book "The Truths We Hold", on January 8. Harris' declaration of a White House run, while dispensing with the exploratory committee preamble, was timed with the Martin Luther King Jr.
Harris paid homage to Chisholm's historic campaign by using a similar color scheme and typography in her logo and promotional materials. "We're already organizing!" Lewis wrote. In 2018, the senator visited Iowa and SC to stump for local candidates.
Beyond South Carolina, Harris allies hope she could pull off a strong finish in Nevada, her neighboring state, and then her home state of California, which has moved its primary up to March 3.
Elizabeth Warren is running for the Democratic presidential nomination on a platform to reduce economic inequality and racial injustice. Harris is also the first Indian American Democrat - of either gender - to try for the job.
Despite being opposed to the death penalty, as attorney general Harris fought to uphold it as a matter of California law. Served as the district attorney of San Francisco from 2004 to 2010.
Vermont Sen. Bernie Sanders, who unsuccessfully sought the 2016 Democratic nomination, is considering a campaign.
A vocal critic of President Donald Trump, Harris called his border wall "a vanity project", and described the partial government shutdown - now the longest-running in USA history that has left about 800,000 federal workers without pay - "an emergency of his own creation". Harris has won three statewide elections in California, giving her a potential leg up over opponents planning to compete in the vast and expensive state. The American public wants a fighter, and they want someone that is going to fight like heck for them and not fight based on self-interests. "It's also likely that her record on criminal justice and banking reform as California AG will continue to plague her if she doesn't adopt a more aggressive message and propose big progressive solutions". A campaign spokeswoman said Monday that she could not yet say where specifically in Baltimore operations will be located.