Transcript for Trump visits Baltimore, will tune into the Democratic Debate
And just a short time ago, president trump said he will watch tonight, and he revealed who he thinks is the toughest contender right now on the democratic side. And she'll be center stage. ABC's chief white house correspondent Jonathan Karl with what the president just said. Reporter: One person who says he'll be watching tonight, president trump. It's going to be very interesting. I look forward to going home, I'm going to have to watch it as a rerun. They have all their weaknesses and their strengths. I think that they're very different. You certainly have a lot of different voices up there, but it would look to me like it would be Elizabeth Warren and it looks like Joe maybe will be able to get there, maybe not. And certainly Bernie is there, he's number three. Reporter: The president is clearly annoyed by a wave of recent polls that show him trailing the top democratic candidates. He calls those polls "Phony." But today, in a sign he's taking the numbers seriously, the president's treasury secretary took aim at the democratic candidate on the rise. If you listen to the Elizabeth Warren plan, you know, it is 100% recession, if not worse. Reporter: The president is campaigning on his economic record and he seems to have fears of a looming recession on his mind. He says Democrats are hoping for one. They're going, like, please, please, please let there be a recession, please. They are willing to give up their results because they think it will help them win the election. They are not going to win the election. Reporter: And tonight, over the Houston skyline, the trump campaign is flying a massive banner declaring "Socialism will kill Houston's economy." Jon Karl live on the floor of the debate hall with us tonight. And Jon, you've learned where the president will be when the Democrats take the stage tonight and when he plans to watch. Reporter: Well, David, the president will be wrapping up a Republican retreat in Baltimore, heading back to Washington. And as you heard him say, he plans to watch it on tape. And what's wild here is he's also handicapping the race, he's suggesting that Elizabeth Warren, perhaps Joe Biden or even Bernie Sanders could be his toughest opponent. And he went on to say that he believes that Biden can ultimately win the nomination if he doesn't make a major mistake. Jon Karl on the floor there where the crowd is growing at this hour. Jon, thank you. The debate just a short time from now, I'll be moderating with our George Stephanopoulos and linsey Davis. So, we hope you'll keep it right here on ABC, 8:00 P.M. Eastern. In the meantime, we turn to
This transcript has been automatically generated and may not be 100% accurate.