It was the highest-profile address yet by any presidential candidate.

Against a backdrop of giant American flags and, off to the side, flags from every state and territory, Sen. Kamala D. Harris spoke on Sunday to a crowd estimated at 20,000 people in Oakland, Calif., that flooded a downtown square and spread into surrounding streets.

While Harris announced her presidential bid on Monday, the Martin Luther King Jr. holiday, her appearance in her hometown on Sunday was the ceremonial start.

Against the pomp, her message was blunt.

“Too many unarmed black men and women are killed in America. Too many black and brown Americans are being locked up,” she said, in what was a recurring theme throughout her 35-minute speech.

“Our criminal justice system needs drastic repair. Let’s speak that truth.”

Later, she raised the fears that nonwhite parents have for their sons and the schooling they impose to try to protect them from danger from law enforcement or others.

“I’m running to fight for an America where no mother or father has to teach their young son that people may stop him, arrest him, chase him or kill him because of his race,” she said.

‘My whole life, I’ve only had one client: The people’

Harris, 54, infused her speech with her biography — the daughter of a mother who emigrated from India and a father who emigrated from Jamaica, the first to research breast cancer and the second an economics professor.

She spoke on a stage outside Oakland City Hall, nine miles from where she went to elementary school just after busing was instituted to increase integration. The stage was five miles from the yellow duplex where she grew up and four miles from Rainbow Sign, a black cultural center where she went as a young girl to cook, dance and hear prominent black leaders.

It was also less than a mile from the Alameda County district attorney’s office, where she began her legal career as a prosecutor.

“My whole life, I’ve only had one client: The people,” Harris said. She repeated the language prosecutors use in a courtroom — “for the people” — which has become her campaign slogan.

But it also carries some risk. Harris followed her tenure in Alameda County with positions as the San Francisco district attorney and the state attorney general. Critics have used a hashtag — #KamalaisaCop — to criticize her record as a prosecutor, suggesting she was too tough on the accused.

Responding to Trump

She framed her campaign as a response to President Trump, highlighting how he has divided the country and attempting to make the case that she would unite it.

“People in power are trying to convince us that the villain in our American story is each other,” she said.

“But that is not our story. That is not who we are. That’s not our America. You see, our United States of America is not about us versus them. It’s about ‘we, the people.’ ”

She mocked Trump’s foreign policy: “We have foreign powers infecting the White House like malware.” She ridiculed his immigration stance: “When we have children in cages, crying for their mothers and fathers, don’t you dare call that border security — that’s a human rights abuse. And that’s not our America.”

In implicit rebukes to a president known for falsehoods, she repeatedly said she would be an honest broker.

“Seek truth, speak truth and fight for the truth,” she said. “If I have the honor of being your president, I will tell you this: I am not perfect. Lord knows, I am not perfect. But I will always speak with decency and moral clarity and treat all people with dignity and respect. I will lead with integrity. And I will tell the truth.”

A look at her agenda

Polls have found that many Democratic voters have no clear view of who Harris is or what she stands for. So in addition to delivering a serving of her biography and a response to the Trump administration, she also sought to outline some of her agenda.

She advocated a Medicare-for-all plan, a tax proposal that would reverse the Republican-passed tax cuts and instead provide middle-class families with tax breaks of up to $500 a month, making pre-K access universal and making college debt-free.

Harris has some significant advantages that have fueled early enthusiasm about her prospects. She has a strong fundraising base in a primary contest most estimate will cost upward of $100 million. Her life story gives her not only entree to black voters who make up a significant share of the Democratic primary electorate but also Asian American voters whose ranks are growing.

But now she must go from running races in California — driven by money and television — to contests in states such as Iowa and New Hampshire, where voters expect intimate campaigning. She is planning to travel to Iowa on Monday, but largely to participate in a CNN town hall, a format that has aggravated some Iowa Democrats who suggested she is using the state as a stage for a national campaign. Tickets are being handed out to a select group of people, which has left others clamoring to interact with the newest candidate.

How she compares to other Democratic contenders

Some of the other Democrats in or considering the race have a more defined pitch. Sen. Elizabeth Warren (Mass.) has leaned heavily on economic populism, while Sen. Kirsten Gillibrand (N.Y.) has made a concerted effort to tap into feminist energy and anger simmering since the #MeToo movement began.

Former San Antonio mayor Julián Castro and South Bend Mayor Pete Buttigieg come from a younger generation arguing that it’s their turn. Former vice president Joe Biden is making the case for restoring political order, while Sen. Sherrod Brown (Ohio) has a message centered on “the dignity of work.”

Harris has positioned herself more as an all-of-the-above candidate, which carries great promise — appealing to segments throughout the party — but also runs the risk of being too ill-defined.

“I think people would be hard pressed to say at the moment, ‘Here is her message, here is why she’s running,’ ” said David Axelrod, a Democratic consultant who helped orchestrate President Barack Obama’s political rise. “That’s a challenge she needs to meet. It’s not enough to be a good candidate on paper, to be in a strategically good position.”

Harris has been relatively untested, having spent only two years in the U.S. Senate. She will have to define herself under national scrutiny.

“If you’re cautious, you come across as that and you seem unrevealing. And people want to know who you are,” Axelrod said.

During her pre-Senate career, Harris was often described as cautious. She responded by saying that she is “fearless, yes. Reckless, no.” During her tenure in Washington, she has been notably more combative, particularly in her treatment of Trump administration nominees appearing before her committees.

Harris’s campaign has been draped in symbolism. After announcing her plans on “Good Morning America” on the King holiday, she held a news conference at Howard University, the historically black college she attended in the District.

On Friday, she traveled to South Carolina, an early-voting state, to greet members of Alpha Kappa Alpha, a sorority she joined in college and whose members she hopes will provide a volunteer corps of supporters.

Several other candidates, including Warren and Gillibrand, have formed exploratory committees that allow them to begin raising money and building a campaign apparatus as a preliminary step before formally entering the race.

Harris, Castro and former congressman John Delaney of Maryland skipped that step and jumped, officially and legally, directly into the race.

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