ROBERT SIEGEL, HOST:
Donald Trump and Hillary Clinton come face to face in their first debate tonight. They'll be onstage for 90 minutes - no breaks, no teleprompters. And we begin today with two of our campaign reporters for a preview.
NPR's Sarah McCammon covers the Trump campaign, and NPR's Tamara Keith covers the Clinton campaign. They are both at the debate site, Hofstra University in Hempstead, N.Y. Welcome to both of you.
TAMARA KEITH, BYLINE: Thanks.
SARAH MCCAMMON, BYLINE: Hi there.
SIEGEL: The campaigns have not said much about how these candidates are preparing, but what have you learned about their approach to this debate? Tam, let's start with you.
KEITH: Well, the Clinton campaign says that Hillary Clinton took preparations very seriously. She's been studying briefing books and doing some mock debates. Though they, as you say, really aren't saying that much about it.
SIEGEL: And Sarah, what about Donald Trump's approach?
MCCAMMON: Also not saying much, but we know that Donald Trump didn't take a lot of time off last week. He was on the campaign trail almost every day and mocked Hillary Clinton for taking a break on Twitter. So that's about all we know of Donald Trump. Although he has said that he will be practicing.
SIEGEL: Now, we've seen these candidates in many debates before throughout the primary season, not to mention the dozens of debates Hillary Clinton had in 2008 in that primary season. Tam, having watched all of those debates, what are the biggest challenges facing these candidates tonight?
KEITH: Well, certainly for Hillary Clinton a challenge is keeping her answers shortish and not getting too deep into the policy weeds. Here's an example of sort of the challenge that she faces. This is from a CNN debate in April where she was asked about banking regulations.
(SOUNDBITE OF ARCHIVED RECORDING)
HILLARY CLINTON: I believe, and I will appoint regulators who are tough enough and ready enough to break up any bank that fails the test under Dodd-Frank. There are two sections there, and if they fail either one - that there is systemic risk, a grave risk to our economy - or if they fail the other that their living wills, which is what you're referring to, are inadequate.
KEITH: So she's a former senator, former secretary of state. She knows a lot of things. And the challenge that she faces is sort of spitting them out in a way that it makes her appeal to voters and someone that they can connect with.
SIEGEL: And Sarah McCammon, from what you've been observing about Donald Trump, what do you see as his biggest challenge tonight?
MCCAMMON: It's really sort of the flip side of that. You know, Donald Trump was really good at sort of stealing the show during the primary debates with sort of big moments and, you know, quips and sometimes insults exchanged with his rivals.
But when it came to longer policy conversations, we sort of saw him clam up, especially in some of the later debates. He almost seemed to disappear during some of those primary debates when it turned to policy. So his challenge is to look presidential, to look more serious and to talk about policy in a way that can compete with Hillary Clinton.
SIEGEL: Well, one of the biggest questions heading into the debate tonight is what kind of temperament we'll see from Donald Trump. Sarah, what are you watching for?
MCCAMMON: You know, there are really two Trumps. There were kind of those two Trumps I just alluded to in the primary debates. And especially since he's clinched the nomination, we've seen him sort of - the teleprompter Trump that has popped up as he's been urged to keep it sort of more serious and then, you know, the sort of - the Trump that you see at Donald - or at rallies - the Donald Trump rallies.
You know, for example, during one of the primary debates, he traded some name calling with Florida Senator Marco Rubio on a Fox News debate in March. Let's listen to that.
(SOUNDBITE OF ARCHIVED RECORDING)
DONALD TRUMP: He hit my hands. Nobody has ever hit my hands. I've never heard of this one. Look at those hands. Are they small hands?
(LAUGHTER, CHEERING)
TRUMP: And he referred to my hands. If they're small, something else must be small. I guarantee you there's no problem. I guarantee.
MCCAMMON: So that's one Donald Trump. Then there was the Fox News debate in January where Texas Senator Ted Cruz had criticized New York values as being too liberal, he said. Trump hit back, talking about how New York had recovered from 9/11.
(SOUNDBITE OF ARCHIVED RECORDING)
TRUMP: And we rebuilt downtown Manhattan. And everybody in the world watched, and everybody in the world loved New York and loved New Yorkers. And I have to tell you. That was a very insulting statement that Ted made.
(APPLAUSE)
MCCAMMON: So that was a rehearsed moment, clearly something he'd planned to say ahead of time. And he can really deliver a punch when he's prepared.
SIEGEL: The statement in question was being critical of New York values. NPR's Sarah McCammon and Tam Keith, thanks to both of you.
KEITH: You're welcome.
MCCAMMON: Thanks. Transcript provided by NPR, Copyright NPR.