Transcript for Bernie Sanders joins the 2020 presidential race

Vermont senator Bernie Sanders officially announced today he's running for president again. In a video, he says he started the political revolution in 2016 and that he now wants to finish it. He joins a growing field, 11 other candidates already in the race on the democratic side. And tonight, what president trump is now saying about Bernie Sanders running. And what we know about Joe Biden tonight. ABC's Mary Bruce on the race for 2020 already. Reporter: Tonight, Bernie is back. I'm running for president. Reporter: The Vermont senator sparked a Progressive movement in 2016, taking on the establishment and Hillary Clinton. The American people are sick and tired of hearing about your damn e-mails. Thank you. Me, too. Me, too. Reporter: But this time around, he's got more competition. Some who also support his old rallying cries, like medicare for all and free college tuition. You know what's happened over three years? All of those ideas and many more are now part of the political mainstream. Reporter: Senator Elizabeth Warren this weekend unveiling her plan for universal childcare. America's middle class is under attack. Reporter: But other democratic candidates are blunt about some of these Progressive promises. I am not for free four-year college for all, no. Thank you. Let me ask you then this, because -- And I wish -- if I was a magic genie and could give that to everyone and we could afford it, I would. Reporter: And while Sanders calls himself a democratic socialist, his opponents, like senator kamala Harris, want no part of that label. I will tell you I am not a democratic socialist. Reporter: But Sanders' fans are still feeling the Bern. On the first day of her campaign, Harris raised $1.5 million. Sanders today raising $1.2 million in just the first three hours. Still this year, Sanders faces another hurdle. He is up against six female democratic candidates while facing accusations from women who worked on his 2016 campaign about sexual harassment by male staffers. The senator has publicly apologized. All right, so, let's get to Mary Bruce, she's live up on the hill tonight. And president trump was asked today about Bernie Sanders. The president saying, quote, personally, I think he's missed his time, but I like Bernie, is what the president said. And a lot of talk about one Democrat who is still on the fence, former vice president Joe Biden. This was the video, Mary, you saw this weekend, getting a lot of attention. The president of armia on the left. He said, are you running? But it was really hard to sort of lead for Joe Biden's answers there, so, what are we hearing from Biden's team tonight, is he running, when will he announce? Reporter: Well, publicly, David, Biden says he has not made a decision yet. He says he thinks there's a tendency in the U.S. To start this process too early. But he will have a decision to announce, soon. And sources to the former vice president tell us they get a sense that he is likely to run. All right, stay tuned. Mary Bruce tonight. Mary, thank you.

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