Transcript for Trump: List of Supreme Court possible contenders is 'outstanding'

Tonight, Democrats on capitol hill are scrambling. They say Republicans have just a one-vote majority in the senate, and that this nomination should wait untilfter the midterms. But Republicans say no way. So, is there anything Democrats can do to slow down president trump's pick? And what it's about to do to an already crucial midterm election. ABC's chief white house correspondent Jonathan Karl on that part of the story tonight. Reporter: It's the reason many conservatives came to support Donald Trump in the first place, his promise to trance tans form the supreme court. And now, that moment may be here. We will begin our search for a new justice of the united States supreme court. That will begin immediately. And hopefully, we're going to pick somebody who will be as outstanding. Reporter: He's made no secret about what he'll do. During the campaign, he promised to pick pro-life judges, and today, he said he will choose from a list of 25 conservatives the white house put out last year. Highly intelligent. Hopefully tremendous people. I think the list is very outstanding. Reporter: Today, I talked to the man who helped the president come up with that list, Leonard Leo, the long-time head of the conservative federalist society. It's a transformative opportunity for the president, for the country. Reporter: To transform the supreme court? Well, to transform the rule of law in our country. Reporter: It will be an epic battle. Republicans have just a one-seat majority in the senate, and Democrats are insisting there should be no confirmation vote until after the midterm elections. Millions of people are just months away from determining the senators who should vote to confirm or reject the president's nominee, and their voices deserve to be heard now. Reporter: The Republican senate leader say there must be no delay. We will vote to confirm justice Kennedy's successor this fall. Reporter: It was Mcconnell who blocked a vote on Barack Obama's nominee Merrick Garland until after the 2016 presidential election. And then, he orchestrated a change in senate rules. The so-called nuclear option, to get president trump's pick, Neil Gorsuch, confirmed with a simple majority vote. The Republican majority is even slimmer now, and tonight, the pressure on these three Democrats is enormous. They defied their party and voted for Gorsuch, and now, they are all up for re-election in states that trump won big. All right, so, let's get to Jon Karl, with us live tonight from the white house. And Jon, as you just reported there, the president has a list of 25 possible nominees now. When is he expected to make this decision and I gather it will come pretty quickly? Reporter: David, I expect this decision could come within the next few weeks, if not sooner. And this list is the reason why he can do it so quickly. His list of 25 conservatives that he says he will choose from. These are people who have already gone through a vetting process, in fact, he has already interviewed a couple of them back when he decided last year to pick Neil Gorsuch. He wants to do this quickly, because he wants to get his nominee confirmed before the midterm elections. All right, Jon Karl, stay tuned. I want to bring in Dan Abrams. Dan, a lot of reporting already on this, about what then candidate Donald Trump said in the third debate, often a pivotal debate. He was asked by the moderator, Chris Wallace, and this was the actual question, do you want to see the court overturn roe versus wade, and here's what he said. Well, if we put another two or perhaps three justices on, that's really what's going -- that will happen. And that will happen automatically, in my opinion, because I am putting pro-life justices on the court. So, bottom line, Dan, how likely is this? Reporter: It seems clear that roe versus wade is as vulnerable as it's been, but that doesn't necessarily mean that it's overturned. Justices are differential toll cases they have already ruled on. The opinion could get gutted, which would mean, as a practical matter, it becomes nearly impossible for women in certain states to get abortions, but we'll have to see. Certainly the most vulnerable it's been in many years. Reporter: Absolutely. I wanted to put this up on the screen, because we talked about how justice Kennedy was a crucial swing vote. Sided with conservatives and citizens united, on the second amendment, on voting rights. But then sided with liberals on gay rights, abortion and affirmative action, so, he was a key player in the court for decades. Reporter: That's right, he was. Now the question is, what happens with chief justice Roberts? Meaning, does he become a potential swing vote? He's not going to be Kennedy. I don't think anybody expects that, but he's so respectful of the institution of the court, and as a result, the question is going to be, does he fight to keep precedent on the books, in effect? And as a result, will he end up splitting from some of his conservative allies, will he evolve? We'll just have to see. Dan, thank you. Our thanks to Jon and Terry, as

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