Transcript for Beto O'Rourke joins pool of 2020 presidential candidates

half hour. George. Now to that breaking political news, a brand-new Democrat in the race for the white house. Former Texas congressman Beto O'rourke, the social media phenom who lost his race for the senate last year joining the growing field just moments ago campaigning in Iowa today and ABC's Paula Faris already there in Des Moines. Good morning, Paula. Reporter: Beto O'rourke is now the 15th Democrat to put his name in the hat. He's expected to hold his first official campaign event here in Iowa a little bit later today and he promises to run a very positive campaign. Amy and I are happy to share with you that I'm running to serve you as the next president of the United States of America. Reporter: This morning Beto O'rourke is joining the 2020 The only way for us to live up to the promise of America is to give it our all. Reporter: The former Texas congressman skyrocketing onto the national political scene when his senate race caught fire in 2018. Thank you, El Paso, thank you, Texas. Reporter: Despite his loss to Ted Cruz, the rock 'N' roll loving 46-year-old caught the nation's attention. ?????? his off beat social media posts appealing to a younger generation, even taking skateboarding at what a burger. His candidacy winning the endorsement of celebrities like Beyonce and now appearing on the cover of "Vanity fair." The star politician weighing his options saying you can probably tell that I want to run but until now his indecision on a white house bid even left many including Oprah asking the By god, when are you going to know the answer? Reporter: When I caught up with him at a Dallas rally in October he told me he would never run. Is there a scenario where you run for president in 2020 or beyond? No. Unee give lick I you will never run for president. No, period. All right. Reporter: Conservatives say he drips with white male privilege and wealth and some are wondering whether or not he's the street fighter they want or need. But there will be two big parts of his platform, those will be health care for all and climate change, George. You will see him in action in Iowa today. Thanks very much.

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