Transcript for Former President Barack Obama campaigns for Joe Biden in Pennsylvania
this race stands in the key state of Pennsylvania. A couple of new polls out tonight. And ABC's Mary Bruce leading us off. Reporter: With Joe Biden off the trail preparing for the debate, tonight, his team sent in its heaviest hitter to the state that's become an absolute must-win. If you just work as hard as you can over these next 12 days, I'm confident we're going to have a good outcome. We're going to have Joe Biden as the next president of the united States. Reporter: Former president Barack Obama in Pennsylvania, holding his first in-person campaign event, a drive-in rally in Philadelphia. This is reality. And the rest of us have had to live with the consequences of him proving himself incapable of taking the job seriously. At least 220,000 Americans have died. Reporter: Biden's team is banking on a huge turnout in Philadelphia and its suburbs and hoping Obama will help energy African-American voters. The truth is, is that I'm very proud of my presidency, but I didn't immediately solve systemic racism by virtue of me being president. Reporter: Trump has been campaigning hard in Pennsylvania. Overnight, rallying his supporters in Erie -- begrudgingly. You know what? Four or five months ago, when we started this whole thing, because, you know, before the plague came in, I had it made. I wasn't coming to Erie. I mean, I have to be honest, there's no way I was coming. I didn't have to. Reporter: Down in the polls, tomorrow night's debate could be trump's last best chance to change the direction of this race. In an effort to limit the relentless interruptions that dominated the first showdown, this time, the microphones will be muted, some of the time, when it's not the candidates' turn to answer questions. I think the muting is very unfair. Reporter: Biden telling our ABC news affiliate, WISN, he knows the debate is going to get ugly. He's kind of signaling that it's all going to be about personal attacks. But I'm going to try very hard to focus on the issues that affect the American people and talk to them. Reporter: On "The view" today, Jill Biden says she's prepared for the president to attack her husband and son, hunter, but she calls it a distraction. You know, as a mother, I mean, I don't -- it really -- I don't like to see my son attacked and certainly I don't like to see my husband attacked. The American people don't want to hear these smears against my family. The American people are struggling right now. Reporter: Biden has been laser-focused on the pandemic, casting it as the president's biggest failure. With covid, is there anything that you think you could have done differently, if you had a mulligan or a do-over on one aspect of how you handled it, what would it be? Not much. Look it's all over the world, you have a lot of great leaders, a lot of smart people, it's all over the world, it came out of China, China should have stopped it. Reporter: As he prepares to take on Biden at the debate, the president is lashing out at "60 minutes," after he cut short their interview. You have to watch what we do to "60 minutes," you'll get such a kick out of it. You're going to get a kick out of it. Lessley Staal is not going to be happy. Reporter: Tonight, the white house chief of staff as criticizing Stahl as an opinion journalist. Let's get to Mary Bruce live in Philadelphia. And Mary, Pennsylvania so key, explains why president trump was there tonight, why former president Obama is there tonight. Two new polls out of Pennsylvania, one with Joe Biden leading, one eight points, the other a little more. Of course, it's always a good bet to look at the average of polls over the last several days. So, where do things stand in Pennsylvania? Reporter: Well, David, the polling average has Joe Biden up here by six points. This is the state that is most likely to determine the outcome of this election. But despite Joe Biden's lead, everyone is treating this state like it is neck and neck. Former president Obama unloading here tonight on president trump, ripping into him on everything from the pandemic to trump's taxes and is treatment of the military. David? Of course, president trump in North Carolina tonight.
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