VIDEO: Sen. Kamala Harris answers questions at Howard University after announcing she's running for president

WASHINGTON -- As Americans commemorate Martin Luther King Jr., Democratic presidential hopefuls are fanning out across the country to honor the civil rights leader and make themselves heard on the national stage.

MORE: Kamala Harris: 'I am running for president of the United States, and I'm very excited about it'

California Sen. Kamala Harris used the holiday to launch a presidential campaign that, if successful, would make her the first woman and the second black candidate to become president.

Harris, who grew up in Oakland, California, and is a daughter of parents from Jamaica and India, is one of the earliest high-profile Democrats to join what is expected to be a crowded field.

MORE: Who is Kamala Harris? What to know about the presidential candidate

"I am running for president of the United States," she said. "And I'm very excited about it."

Harris spoke out against President Donald Trump and the government shutdown while answering questions at her alma mater, Howard University in Washington D.C., on Monday. She said: "He is now holding the American people hostage over a vanity project that he calls a wall while 800,000 people are trying to figure out how they're going to pay their rent, how they're going to pay their mortgage. It is completely irresponsible. Those folks don't want a wall, they want a paycheck."

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