Transcript for Bernie Sanders announces 2020 presidential run

much. Now to breaking political news. Bernie Sanders announcing he's running for president again. His challenge fell short in 2016 and the feel much more crowded this time around. Terry Moran has the latest. Good morning, Terry. Reporter: Good morning, yes, it's official, Bernie is back and the last time Bernie Sanders ran for president, when he announced hardly anybody noticed and then he ignited that astonishing grassroots movement and changed the democratic party, shifting it decisively leftward but now the question is, at 77 years old, can Bernie bottle that lightning again? This morning, senator Bernie Sanders is making it official. Together you and I and our 2016 campaign began the political revolution. Now it is time to complete that revolution and implement the vision that we fought for. Reporter: Sanders sent this message letting them know he's getting back in the ring. Is improbable run in 2016 gives him an edge in name recognition for 2020. He started that race as a little-known independent senator from Vermont. I know that if I do this, I start off as a significant underdog. Reporter: But his Progressive platform, universal medicare for all, free tuition at state colleges and universities, trillion dollars in infrastructure spending caught fire as thousands flocked to his rallies hoping to feel the Bern. We need a political revolution. He struggle theed to win African-American in states like South Carolina and he ultimately conceited to Hillary Clinton at the democratic national convention. I move that Hillary Clinton be selected as the nominee of the democratic party for president of the United States. Reporter: But in a crowded 2020 field polls show him near the top of the contenders. Bernie Sanders begins this campaign dealing with an issue from the last one, Sanders has now twice apologized to women staff members who say they were harassed or mistreated during the last campaign. That's bound to come up again but the real question for Bernie Sanders, George, of course, is having ignited this Progressive movement in the democratic party, can he now take advantage of it, take it all the way and win. Because so many other candidates have his ideas right now, Terry, thanks very much.

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