"The future of our country depends on you and millions of others lifting our voices to fight for our American values".
Harris so far appears to be the only significant entrant from California, a state with vast resources for a favorite-daughter candidate.
Before her 2016 victory in the Senate race, Senator Harris served as the district attorney in San Francisco before she was elected to serve as attorney-general.
Since Harris sits on the Senate Intelligence Committee, Stephanopoulos also asked if she has seen any evidence from special prosecutor Bob Mueller's investigation that would warrant impeaching Trump.
Her announcement has been described as "historic" by Vox, with many Twitter pundits seemingly in agreement. Harris said transgender people "for too long" have "been the subject of bias, and frankly a lack of understanding about their circumstance and their physical needs, in addition to any other needs they have".
Then in January 2017, she took the oath of office as California's junior United States senator, making her the first woman of South Asian descent (her mother is a Tamil Indian) and only the second black woman senator in American history, after Carol Moseley Braun.
Her campaign could be aided by the schedule for the state-by-state party nominating process that is scheduled to begin in February 2020.
It's no accident that Harris, whose mother is from India and father from Jamaica, chose Martin Luther King Jr. She's portraying herself in a campaign video as a fighter for justice, decency and equality - values she says are "all on the line".
Senator Kamala Harris (D-CA) speaks to the media after announcing she will run for president of the United States at Howard University in Washington, U.S., January 21, 2019. We know that we've not yet reached those ideals, but our strength is that we fight to reach those ideals. "And it was about a belief that we are a country that was founded on noble ideals and we are the best of who we are when we fight to achieve those ideals", she said.
After arriving in the Senate in 2017, Harris quickly leveraged her seat on two high-profile Senate committees to become a national figure. And her campaign will be family affair: her sister Maya Harris, who was an adviser to Hillary Clinton's 2016 presidential campaign and served as the executive director of the ACLU of Northern California, will serve as Harris' campaign chair.
A recent NPR/PBS Newshour/Marist poll found that a majority of Americans, 54 percent, have not yet formed an opinion of Harris.
Harris' home state of California has also moved up its primary to Super Tuesday-but that will also be a tough battle given the expense of driving a message on television in the Golden State.
Harris's announcement comes about a week after New York Sen. Kirsten Gillibrand. Both senators' announcements have been met with skepticism, the former as a result of her "divisive" claim to Native American ancestry, which she inflamed through her "1/1,024th" DNA test fiasco, and the latter because of her poor performance in the presidential polls. The first member of the tiny minority community to run for White House was Bobby Jindal, the Republican governor of Louisiana. There's no apparent front-runner at this early stage and Harris will face off against several Senate colleagues. Harris is also the first Indian American Democrat - of either gender - to try for the job.
Harris also cited her years as a prosecutor in asserting: "My entire career has been focused on keeping people safe".