As Donald Trump and Hillary Clinton prepare to take the stage Monday for the first of three debates before the election, RealClearPolitics spoke with two veterans of the Republican primary about their impressions after having faced Trump in that setting.

Michael Steel, a former senior adviser to Jeb Bush, and Frank Sadler, Carly Fiorina’s campaign manager, pointed to Trump’s debating style — confident, if vague on details — as his greatest asset. “I think it’s a combination of skills honed over his years as an entertainer — a combination of bravado and shamelessness,” said Steel.

They agreed Trump has an unusually good ear for sound bites and confrontations that will capture the media’s attention, often to his advantage. Meanwhile, they noted his uncanny ability to dodge details, or even his own past statements, without consequence.

Both were struck by a moment during the second GOP presidential primary debate, hosted by CNN at the Ronald Reagan Library, when conservative radio host Hugh Hewitt asked Trump what his priority would be among the nuclear triad, meaning would he beef up the land, sea, and air missiles that can deliver nuclear warheads. Trump, apparently unfamiliar with the term, spoke for a few minutes about nuclear proliferation and the Iraq War, before concluding: “Nuclear is just the power — the devastation is very important to me."

A response like that might have been damning for another candidate, but it did not stick to Trump — foreshadowing fundamental challenges on the debate stage for his GOP rivals, and now Clinton.

Michael Steel, former senior adviser to Jeb Bush:

[Trump] managed to come up with words that sort of formed sentences, but [when] asked a very specific policy-based question, an important one, he had no response. He managed to string together words. He never gets that deer-in-the-headlights look, even when he clearly does not know what he’s talking about. I don’t remember him ever being flummoxed.

At the North Charleston debate, he had an answer on Boeing and trade jobs that showed some preparation [Boeing is a major employer in South Carolina and there have been tensions over an attempt to unionize the workers. Trump said in the debate that these jobs could move to China.] It’s an obvious attack given the huge Boeing plant right up the road from that venue, that these are good-paying SC jobs that you’re essentially going to throw away. And he had a response about Boeing now having to do manufacturing in China. And what he said wasn’t accurate, but it had a kernel of truth to it and was based on a relatively recent news story, which suggested to me he was doing some kind of traditional debate prep, in the sense that that was an obvious attack given the location and he had a factual-ish response.

Secretary Clinton needs to be prepared for Trump to say things that are wildly factually inaccurate. I think she needs to be prepared for the fact that he is most dangerous when he is on the defensive. If she feels like she lands a blow or is scoring points, that’s when they need to be most worried about him launching a personal attack or saying something outlandish.

[A debate moderator needs to have] a big personality, because in addition to being completely fluid on the facts, [Trump’s] perfectly happy to walk over you. He’s got a lot of skills of an entertainer, of a television personality, that make it very difficult for traditional candidates to debate him.

He hates being told he’s wrong, he hates being challenged factually or those kind of things, but I don’t recall him ever losing his temper. He’ll roll his eyes, he’ll interrupt, he’ll talk over people. Those are a lot of things that would not traditionally be considered presidential, but I don’t remember him hurting himself that badly. People expect him to be undisciplined, and I don’t recall him ever really having a bad moment like that.

Trump does his worst when there’s that consistent focus on him. A strong, well-informed moderator and a single opponent is probably a much worse format for Donald Trump.

Frank Sadler, former campaign manager for Carly Fiorina:

Hugh Hewitt asked Donald Trump about the nuclear triad, which had a very specific answer to it. Trump doesn’t know the answer and gives his made-for-TV answer, and a lot of the people watching think it’s completely great. I know Hugh Hewitt knows the answer to the question. And I do remember feeling like, if that had been Mitt Romney and he had said that, things would have been a lot different. I was like, wow, that’s not the right answer, Hugh Hewitt knows it’s not the right answer, and yet it didn’t seem to matter at the moment.

If the goal is, let’s really understand how these folks are going to tackle policy in the administration, if that’s really what you want, to get somehow a deeper dive into what they think about policy, then I think you probably have to handle the debate differently than if it were Mitt Romney there or John McCain.

The expectation is that, yeah, Donald Trump is going to say something that probably isn’t politically correct, or sexist, or was a little off the cuff, but [viewers seem to let him off the hook and tell themselves] that’s not really what he means, he’s just not as articulate. With Mitt Romney, everything was scripted, so anytime he misspoke it was a much bigger deal.

Absolutely to his credit, [Trump] has a very good grasp of how to handle the spotlight, how to handle the media. I don’t mean that in a condescending way to the media, but he’s very gifted at understanding how to take advantage of those moments. It’s different than how other people have done it, and he’s very astute at that.

If the debate is not about diving deep into policy, really getting in the weeds on this stuff, I do think this is set up much better for Donald Trump than it is for [Clinton]. It’s weird to use this word, but he is authentic. You are seeing who he is, right? Take it or leave it, it is what it is. Hillary has been immersed in the policy world for 30 years. She’s incredibly studied. She knows this stuff. She’s brilliant when it comes to policy. I don’t agree with her policy stances, but I absolutely think that she’s given serious thought over the years to policy. If the debate is about how you make one policy decision over another, that’s fine, she’ll be great. I don’t suspect that’s what this is, and so this is about relating to the voter. I think being authentic is much more valuable than simply knowing all the right answers. She knows all the right answers, I just don’t think she’s particularly authentic.

I do think he understands how to capture those 30 seconds or 90 seconds and not get hung up on what the press wants him to say, or what the policy wonks at [the] Heritage [Foundation] want him to say, or what I want him to say. I think he’s very gifted at understanding … the American people, and authenticity means more to them. He really is good at coming across as authentic. Debate prep doesn’t solve that, if that’s your problem.