Transcript for 'I'm in this fight all the way': Warren announces 2020 run

Back here at home, and the 2020 presidential race jumpstarted. Massachusetts senator Elizabeth Warren already announcing she's in, but she's not alone. Here's ABC's David Wright. Reporter: As she announces her first big campaign swing through Iowa, senator Elizabeth Warren is trying to showcase how relatable she is. Hold on a sec. I'm going to get me a beer. Reporter: Cracking a cold one on this new year's livestream with supporters. The video also featured her husband and their 8-month-old puppy. Hours earlier, Warren announced her intentions on Facebook. America's middle class is under attack. Reporter: President trump is not impressed. I'd love to run against her. She says she's in the fight all the way. Do you really think she believes she can win? Well, that I don't know. You'd have to ask her psychiatrist. Reporter: There's a growing list of possible democratic hopefuls. Former vice president Joe Biden said this week he'll make up his mind in the next two months. Senators kamala Harris, Cory booker and Kirsten Gillibrand are already reportedly staffing up. Vermont senator Bernie Sanders hasn't ruled out running himself. And the big wild card, outgoing congressman Beto O'rourke. Will he get into the race? Over new year's, O'rourke tweeted out this picture, building an igloo with his wife and kids. And David Wright joins us now. David, senator Warren making it official, and this weekend, she's heading to Iowa? Reporter: That's right, Tom. She has four big campaign events planned across the state. Really trying to take advantage of this moment, when she's the biggest named challenger to declare her intentions. Tom? David Wright for us. David, thank you.

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