Transcript for Beto O'Rourke kicks off 2020 presidential campaign in Iowa

Thanks. We turn to that growing list of Democrats hoping to take on president trump. Paula Faris went one-on-one with the latest candidate to join the ranks former Texas congressman Beto O'rourke. Good morning, Paula. Reporter: Good morning to you, George. Not that long ago he told me there was no scenario win or lose that senate seat he would run for president in 2020. But as he crisscrossed the state we asked what changed his mind and his relative lack of experience. The next president of the United States. Reporter: Beto O'rourke kicking off his 2020 bid in Iowa and we were right there as he canvassed the state calling for unity. Hey, everybody, what's up? Doesn't matter whose team you are on today, doesn't matter which prospective nominee you back. Reporter: The 46-year-old tireless on the trail hours after his "Vanity fair" cover story and his official announcement with wife Amy by his side. The only way for us to live up to the promise of America is to give it our all. Reporter: It's been four months since that failed senate race against Ted Cruz when he told number ruse outlets including us that he'd never run for president. You weren't going to run. What made you change your mind. I have something to add and my country, my kid depends on us doing everything we can. For me that's running for president. Reporter: Already facing tough questions including his readiness for the job, his six years in congress largely One criticism you don't have any significant legislation attached to your name. We know you can fund raise and campaign. Why should voters be confident you can govern. I was able to work with Republicans, I was even able to work with this administration to get legislation passed. We always work together and we find our common purpose and common cause and get after it. Reporter: So unity and positivity that, is his campaign platform. Whether or not it's a winning strategy to beat trump who you guys, as you know, occasionally likes to street fight but O'rourke tells me it's the only way to run. Still cold in Des Moines. Just a tad. I didn't think it would be this cold in Iowa. I was wrong. That college admissions, new

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