Last night, 10 of 20 qualifying Democratic candidates took part in the first debate of the campaign season. The other 10 go at it tonight. WGBH Radio Political Reporter Adam Reilly spoke with WGBH’s Aaron Schachter about what came out of night one and what to expect heading into night two. This transcript has been edited for clarity.

Aaron Schachter: Okay, so, a recap, if you would, of what happened last night.

Adam Reilly: Well to my mind, the biggest thing to happen was Elizabeth Warren, our Massachusetts senator, coming out and saying that she believes it's time to get rid of private health insurance.

"Look at the business model of an insurance company," Warren said. "It's to bring in as many dollars as they can in premiums and pay out as few dollars as possible for your health care. That leaves families with rising premiums, rising co-pays."

Now Warren has indicated before that she backed so-called single payer health care, a.k.a. “Medicare for All,” but this is the most aggressive and explicit that she's been when it comes to saying, 'Yeah, we're going to end private insurance.' There are a lot of people who think this might have been a mistake for her, that it opens her up to attack ads from Democratic opponents or a possible Republican opponent. It's also maybe kind of in keeping with where the base of the Democratic Party has been heading.

I would also say, the big takeaway for me last night was: I was kind of wondering which of the candidates who hasn't really popped might end up getting a little more attention or another look on the heels of this first of two debates. And I think last night it was Julian Castro, who impressed a lot of people. He apparently has gotten a huge uptick in donations, and now is everywhere in the media. Who knows how long it'll last. But I think he was the candidate that made a lot of viewers say, 'Hey, what about that guy?'

Schachter: So that sounds like that was surprising to you. Anything else from last night?

Reilly: I will answer that question by seguing into a confession that I made some predictions about what was going to happen last night that I got wrong, which of course surprised me. I thought that Warren, because she was the only one of the top five candidates to be on the kiddie debate stage on night one, I thought that she was going to get targeted by the other candidates. They would try to knock her down a peg and make themselves look better by making her look a little bit worse. That didn't really happen.

There was a point early on in the debate where it sounded like all the other candidates were actually trying to sound as much like Warren as they could. That faded away in the second half, when I think she actually was called on a little bit less. I also thought that Warren and others were going to be taking a whole lot of pot shots at the candidates who weren't there who are going to be debating on night two.

Schachter: Two of whom are the top two candidates.

Reilly: Yeah, Joe Biden and Bernie Sanders. Then you also have Pete Buttigieg and Kamala Harris. There were maybe one or two of those, but there wasn't nearly as much of that passive aggressive sniping as I had looked forward to.

Schachter: So tonight, what do we think? Passive aggressive sniping or no?

Reilly: Tonight they won’t need to be so passive aggressive because four of the top five are right there. I'm going to double down, even though I totally blew it with predicting about what was going to go down on night one, I’m going to double down here. I think you will see people go aggressively after Biden, in large part because he's not just the front runner in terms of the polls, but he's a guy who has some obvious baggage. He has come under fire for his unusual physical interactions with women. He's come under fire also for waxing nostalgic about the days when you could collaborate with segregationist senators and still get stuff done. And he has this interesting theory of the case, which I've seen him present in New Hampshire, which is: American politics are going to go back to normal if we just get rid of President Trump — you know, if he loses in 2020, then Republicans and Democrats are going to start working well together again. It's a strange theory to have since he was Barack Obama's vice president and it seems to ignore the realities of the Obama presidency. But that's the case that Biden makes, so I expect people to push him on those points and maybe some others.

Schachter: One of the big talking points last night was a tweet from President Trump that just said: "BORING!" How will that affect the debate tonight, do you think?

Reilly: I don't think it will. In fairness to the president, who is an avid student of showmanship, there were times when the debate was a little boring. There were also times when it was pretty interesting, like when Warren was embracing single payer or when Julian Castro was really going after Beto O'Rourke and taking the wind even more out of his sails.