Transcript for Democratic nominees head to Ohio for the 4th 2020 presidential debate
Now to the race for 2020. 48 hours from now, a dozen democratic candidates will crowd the stage for their first debate since the impeachment inquiry began. And today, Joe Biden answering questions about his son. Here's Rachel Scott. Reporter: Tonight, former vice president Joe Biden coming to his son's defense. Why is he just not making the decision to step down from the board of a chinese-backed company? Let's get something straight. First of all, no one, no one, has indicated of any consequence that anything was done wrong or illegally by me or by my son. This is the president flat lying, number one. Number two, the statement my son put out today, which I saw when he put it out, I was told it was going to be put out. I was not consulted about it. It represents the kind of man of integrity he is. Reporter: President trump has criticized hunter Biden for his work with Chinese companies while his father was vice president. Even calling for China to investigate. China should start an investigation into the Bidens. Reporter: Today, in Iowa, Biden committing if he's elected -- No one in my family will have an office in the white house. Will in fact have any business relationship with anyone that relates to a foreign corporation or foreign country. Reporter: Senator Bernie Sanders speaking to Iowa union members from Vermont. He told our Jonathan Karl why she should be the choice over senator Elizabeth Warren. What do you say that they would pick her because she's eight years younger, she didn't just have a heart attack. And, in the positions, you're pretty much the same. I think she's a very, very good senator. But there are differences between Elizabeth and myself. She has said she's a capitalist through her bones. I'm not. Reporter: And the next democratic debate, just two days away. The democratic candidates are coming to terms with the reality that with 12 candidates on a stage, that means there will be less time for them to get their message across. Kamala Harris saying that does not allow for conversation on
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