Transcript for Cory Booker: 'Fighting through the lines of divide' is his 2020 strategy
His public and private life under the microscope. Let's walk up the hill here, because I can tell you -- hey, how you doin'? Have you heard he's running for president? Yeah. God bless you. Reporter: Cory booker can't walk a block from his house without half of Newark turning out to see him. What's up? I left my phone at home plugged in. Can I text myself? Reporter: I've been a journalist for 38 years. I've never seen a candidate for campaign give his cell phone number out to someone on the street. I've been giving my cell phone number out since I started. You fight with the best of who are you, not the worst of who you are. Reporter: This style of retail politics. A pleasure to meet you. Thank you very much. Reporter: Making connections, one person at a time. Our next president. Reporter: Is what booker is betting will take him to the white house. Come on, you got to lean in a little more. Reporter: But in this current environment of nasty politics, can your nice-guy approach win? As a guy who was a chief executive of a major city, I ran a fire department, fighting fire with fire is not a good strategy for putting out fires. Reporter: Booker cut his teeth as a politician in a street fight literally. I'm Cory booker. You ever hear my name? Reporter: His first run for mayor of Newark, chronicled in the documentary called "Street It's time that we pull together. Reporter: He lost that race but proved his political strength when cast as the underdog. He finally became mayor of Newark in 2006, taking on a city deeply mired in poverty, crime, injustice. One of his solutions, private equity. Sparking criticism he was too close to big business. I call out Wall Street, and I have, but when I needed to build the first hotel in 40 years and I needed partners to invest. That created jobs for a lot of people that didn't have them. Reporter: Forgive me, but Newark is still a tough town. It may be better, but this is still a hard-traveled place, Yes. We've made significant progress. The best endorsement for the city in many ways is our population is growing for the first time in 60 years. I don't know if there's any place that's solved all their problems, but Newark from where we were to where we are now is probably one of the most successful stories of a come back you can find in the last decade in America. Reporter: The department of justice found his police department will a pattern of unconstitutional policing. Top brass at the water agency admitted to taking bribes, and the deputy mayor was convicted of conspiracy to commit extortion. I'm the first mayor in Newark that wasn't indicted of something going back to the '60s if not before. Reporter: Is that a badge of honor? That's not a badge of honor. I introduced significant ethics legislation to tie the hands of any future administration and making sure they're doing things right. Reporter: He seems to have a knack for attracting attention. You can't leave your dogs out and go away. Reporter: And rescue the a woman from a burning building, earning him the nickname "Superman." Ellen did give him a Superman suit. Cory's overwhelming optimism might make some people question his motive. Or his intents. I think he's absolutely for real, wants to get the job done and has the ability to do it. Reporter: He played high school football with booker and says he knows his heart. I don't think there's any doubt Cory's been inspirational to a lot of people. He inspired me, and, you know, I've always counted him as someone that I would be friendly with if I saw him on the street. Reporter: Booker grew up here in suburban New Jersey. His parents, IBM executives, preached and practiced high achievement and several When I was a baby, my parents tried to move us into a neighborhood with great public schools, but realtors wouldn't sell us a home because of the color of our skin. Reporter: They didn't run, they integrated the town. They learned a powerful lesson about challenging with dignity. He went on to Stanford university on a football scholarship. A law degree from Yale. His ivy league pedigree lending itself well to the senate to which he was elected in 2013. Please raise your right hand. Reporter: His key initiatives have focussed on justice reform. The only bipartisan legislation to pass under this president was one that I led in the United States senate along with dick Durbin. Reporter: He proposed a plan to curb violence, which would ban assault weapons, create a gun licensing program. And limit the purchase of firearms to one a month. Inspired in part by his adopted neighborhood. Right here, shahad Smith was shot and killed with an assault rifle. I'm tired of walking around cities like mine where you see shrines to dead kids, teddy bears and candles in places where the murders happened. Reporter: Despite being in the public eye for nearly half his life, the 50 year old vegan has kept his personal life private. But earlier this year, he revealed he's dating rosario Dawson. I feel blessed to be dating a person like that. Reporter: Should we set a "Nightline" special? I'm not sure if this is an interview with you or my mom. But I'm excited about our future, and just deeply, deeply grateful. Such a good guy, passionate Definitely at an age where he I realized, you know, life is long, and having a partner makes you better. She's transforming the way I look at the world. She's making me a better person. She's challenging me to be the best me, and I'm not talking about my professional life. My personal life. We, will, rise! Reporter: For now, less renowned than the top contenders, well behind in fund raising, Cory booker has played the unorthodox underdog, smiled his way to victory, again and again. P is America ready for a second black president? I think America is ready for a damn good president who's going to stand up for Americans. Reporter: There's only one former mayor elected to president, grover Cleveland, from Buffalo. And the new officer sworn in
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