Transcript for South Carolina primary draws closer
Now, to the race for 2020 tonight, and the countdown to the South Carolina primary, two days away now. Tonight here, we are one-on-one with former vice president Joe Biden, who has considered south Carolina his firewall. ABC's Mary Bruce with Biden as Bernie Sanders tonight declares he is the most electable against president trump. Reporter: After coming into the race as the front-runner, in South Carolina, Joe Biden is now looking for a comeback. We spoke to him today on his campaign bus. You've said, if you win here, that you will be unstoppable. Bull your rivals disagree. They say even if you do well here on Saturday, that it won't make a difference, that it won't be enough to propel you to win big on super Tuesday and beyond. Well, I'm not a pundit, but let's see. Let's just see what happens. Reporter: It's not too little too late? I don't think so at all. We'll see. Reporter: For Biden, this is deeply personal. At a town hall overnight, opening up about his faith and the loss of his son, beau. My son, beau, was my soul. And -- and what I found was, I had to find purpose. He asked me, when he was dying, promise me, dad, promise me, dad, promise me, I know no one loves me more than you do, dad, but promise me you'll stay engaged. And every morning, I get up and I say to myself, I hope he's proud of me. I hope he's proud of me, because that's the thing that makes me move on. Reporter: The new front-runner, Bernie Sanders, is already looking ahead to super Tuesday. Today, in North Carolina, pointing to the latest polls, he argued he is the most electable. So, don't tell me Bernie can't beat trump. We're going to beat him, we're going to beat him here in north Carolina, we're going to beat him all over this country. Reporter: Sanders is expected to also do well in south Carolina, but with the other candidates splintering the vote, new questions about what comes next. If they don't do well, should your rivals like Pete buttigieg, Amy klobuchar, should they start think about dropping out? I'm not going to tell any other candidate what they should do. I know why I'm running, they know why they're running. I'm going to stay in this because it matters. Mary Bruce is in Charleston, South Carolina, today, and president Obama, as we reported here last night, of course, staying on the sidelines during this race, saying so little, but tonight, we're hearing a little bit more from him and he says he's, in his word, encouraged by the democratic field? Reporter: Yeah, David, the former president seems to be trying to calm some nerves here and tamp down concerns that the democratic establishment won't be able to unite around a candidate. Obama reiterating today that he will, quote, wholeheartedly support whichever Democrat wins the nomination. Mary Bruce, thank you. There is still much more
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