Booker launched his run on Friday morning amid speculation that he would join the race.
Booker, the state's first African-American senator, is the ranking member of the Senate Subcommittee on Surface Transportation and serves on multiple other committees.
The senator made the announcement on Feb. 1, the first day of Black History Month. Booker's black heritage is a major theme in his first campaign video.
"My dad told me, 'Boy, never forget where you came from or how many people had to sacrifice to get you where you are,'" he reflected in the video.
Booker said that when he was young, his parents were unable to buy a home in a neighboorhood with good schools because they were black. He said a group of white lawyers fought for the rights of families, including his, to live where they wanted.
"They changed the course of my entire life," he said. "Because in America, courage is contagious."
Booker joins a crowded field that already includes fellow senators Elizabeth Warren of Massachusetts, Kamala Harris of California and Kirsten Gillibrand of New York. He's the second black candidate in a primary field that's already historically diverse.
"I believe that we can build a country where no one is forgotten, no one is left behind; where parents can put food on the table; where there are good-paying jobs with good benefits in every neighborhood; where our criminal justice system keeps us safe, instead of shuffling more children into cages and coffins; where we see the faces of our leaders on television and feel pride, not shame," Booker said in the campaign video, subtly jabbing at President Donald Trump.
"It is not a matter of can we, it's a matter of do we have the collective will, the American will?" he added. "I believe we do."
Booker is already hitting the ground running with the campaign, with interviews scheduled throughout the day Friday, including an appearance on The View, where his mother plans to sit in the audience.
Due to a recent New Jersey law, Booker will be allowed to run for re-election in the U.S. Senate while running for president in 2020.
Booker has $4.1 million left in his campaign coffers that could also be used to assist his presidential run. A prominent Booker supporter, San Francisco attorney Steve Phillips, says he is working on millions of dollars in committed donations to a so-called super PAC that would boost the senator's candidacy, but Booker's campaign is openly against super PACs playing any role in the presidential race.
The Associated Press contributed to this story.
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