In this week’s politics Slack chat, we get aboard the Donald Trump train and find it … luxurious. The transcript below has been lightly edited. Also, check out the “perfect” Democratic stump speech.

micah (Micah Cohen, politics editor): Hey, everyone! Some Trump questions for today: Does Trump have a ceiling? If he wins South Carolina by a big margin (as polls suggest he will), does he become the heavy favorite to win the nomination? Is the Trump train leaving the station?

natesilver (Nate Silver, editor in chief):

“runaway trump, never goin’ back /

right way on the outsider track /

seems like rubio should be getting somewhere /

somehow cruz is neither here nor there”

micah: CHAT OVER.

clare.malone (Clare Malone, senior political writer): I was going to make a gilded ceiling joke, but the thunder is taken.

natesilver:

harry (Harry Enten, senior political writer): I’d like to note at the beginning of this chat that I won’t curse, as I have learned that my mother reads these. As for the rest: I’ve made a big enough fool of myself throughout this entire process, so I’m hesitant to declare anything. Still, how can you look at the polls and think anything outside of these three outcomes is possible? 1. Trump wins the nomination. 2. Marco Rubio wins the nomination. 3. Contested convention.

micah: Let’s back up for a second. What’s the evidence that Trump has a ceiling? Since he declared his candidacy, his support has only gone up.

clare.malone: Well, his support in South Carolina is at 35 percent, which is what he won in New Hampshire.

natesilver: There’s a fair bit of evidence that Trump is likely to encounter some upward resistance. Which is not quite the same thing as a hard ceiling. In both Iowa and New Hampshire, his favorability ratings were only around 50 percent. In fact, in New Hampshire, about half of Republican caucus-goers said they’d be unhappy with him as their nominee.

clare.malone: I think to his supporters, Trump is a Teflon candidate — he can do no wrong and in fact only gets more appealing when he’s accused of doing wrong.

harry: The idea here is fairly simple isn’t it. Look at the Monmouth University poll that came out as we were sitting here. Trump’s favorable rating is again just 50 percent. His net favorability rating is only +9 percentage points in South Carolina. Rubio’s is +26. The key for Rubio is to get this to a one-on-one race. Anything else and Trump is going to coast.

clare.malone: But I wonder about the broadening out of the race when it comes to March. Maybe he becomes less unstoppable then.

natesilver: We know he has a high floor. He’s proven it with votes. But he may also have a low-ish ceiling. In that sense, Trump’s “momentum” may matter less than it would for another candidate. It’s certainly not true that 100 percent of Jeb Bush’s votes, for instance, would go to Rubio. Trump would get some. But there’s been a lot of evidence from the start that Trump does underwhelmingly as a second choice.

But this is also why it was a good sign for Trump that he got 35 percent of the vote in New Hampshire instead of the 24 percent he got in Iowa. If you’re at 35 percent — well, you don’t need that much more to go from a plurality to an outright majority. At 24 percent, it’s much tougher.

micah: But I remember people saying the same thing about Mitt Romney in 2012 — i.e., “Well, if you combine Newt Gingrich and Rick Santorum’s vote share, that beats Romney.”

harry: Yes, but there is a TREMENDOUS difference. Here’s a GOP national poll from Quinnipiac University from February 2012. With Santorum, Gingrich, Ron Paul and Romney tested, Santorum was ahead 35 percent to Romney’s 26 percent to Gingrich’s 14 percent. When the poll asked about a one-on-one matchup between Romney and Santorum, Santorum’s lead expanded, but only to 13 percentage points. Meanwhile, Romney led Gingrich in a one-on-one by 13 percentage points. In other words, there was no real sign from the polling that Romney was any worse off in a one-on-one than in a multicandidate field. But now look at the data from this year. A Public Policy Polling survey from South Carolina has Trump leading with 35 percent, followed by Rubio with 18 percent. But in a one-on-one, it was Trump 46 percent and Rubio 45 percent. In other words, it’s clear that Trump is benefiting from having the opposition divided.

clare.malone: OK, so Trump’s probably going to win South Carolina by a big margin, probably the same thing in Nevada — to quote Journey, it’s just going to go on and on and on. So what’s a party elite to do? Is this where we show our readers a lot of leg (politically speaking) and talk about contested conventions?

micah: Wait! Before we get to contested … to Clare’s point, are we just left waiting for a two-man race? Is Trump just going to keep winning until then?

harry: Not necessarily. There are still some states he could lose, but if you believe Trump is getting between 30 percent and 40 percent. It’s difficult to beat him if you have two or more opponents.

clare.malone: What are those states, Harry?

harry: North Carolina, Arkansas and Oklahoma, to name a few, judging from polls I’ve seen over the past few weeks.

natesilver: Let me just point out that in the only two states where we’ve gotten actual votes so far, Trump lost one of them. So clearly he isn’t literally unstoppable. But back aboard the Trump train …

micah: All right, we’ll get back to the one-on-one scenario in a second, but what will you all be watching for in South Carolina? Even if Trump wins by 20, are there other things we should be watching for regarding his coalition, the other candidates, etc.?

harry: Well, I think it’s going to be a huge delegate sweep for Trump. When you’re winning by 20 percentage points and doing fairly well across all demographic groups, you’re probably winning (and if you’re not winning, you’re close) in all congressional districts. That means (given the way delegates are allocated in South Carolina) that Trump is going to win all of them and jump out to a fairly sizable delegate lead.

natesilver: The big question is whether South Carolina is the end of Jeb!?

clare.malone: Yah. I think this gets into my latest theory of the ever-fascinating Jeb Bush saga. At first, I thought he was going to stay in through South Carolina and then call it quits. But now I think that he’s gotten the whole family in on the operation and they’re out here to save the party — the Jeb campaign and super PAC are just going to pour as much money as they can into taking Trump down or at least down a notch or two.

harry: I wrote this week’s 2016 newsletter on this: Jeb has the support of Sen. Lindsey Graham of South Carolina and plenty of the establishment in the state. [Editor’s note: Though right as this chat was wrapping up Wednesday, it was reported that South Carolina Gov. Nikki Haley would endorse Rubio.] Still, Bush is doing quite poorly, and there are no signs of Bush doing well anywhere. It’s not as if his train is moving slowly. It’s as if it’s not moving at all.

natesilver: Jeb is now 7 percentage points behind Rubio in the South Carolina polling average. Obviously, we have to see if that translates into actual votes on Saturday. But it’s amusing that the media declared Jeb a winner in New Hampshire and Rubio a big loser when it’s Rubio who’s moved up a bit in South Carolina polls while Jeb’s numbers have been flat to down.

clare.malone: I don’t know if the media declared Jeb a winner.

natesilver: The media certainly declared Rubio a loser, however, and his numbers have recovered pretty nicely.

clare.malone: Yes, that’s true. The debate yips storyline didn’t stick to the wall.

natesilver: It’s important to remember that things like debates often just have temporary effects. The pre-New Hampshire debate happened to be timed remarkably badly for Rubio. But if he hits his polling average in South Carolina, New Hampshire may have proven not to have mattered that much after all. Also worth mentioning that Rubio is a conservative and New Hampshire is a fairly moderate state. In the exit poll there, Rubio did slightly better among conservative voters than moderate ones.

harry: I think what this has proven is that Rubio is the only candidate who can stop Trump. The fact that he melted down on a debate stage and still has the best favorable ratings of any of the candidates who actually stand a chance is telling. (Side note: Ben Carson may actually have better favorable ratings than Rubio because no one is attacking him.)

natesilver: Harry, that’s slightly too emphatic for me. Maybe nobody can stop Trump. But I agree that The Establishment (maybe that should be the name of an emo band?) would maximize its chances by getting Rubio into a one-on-one race with Trump. How do they manage to do that? I don’t know, but they really don’t have time to screw around anymore because some pretty big delegate prizes are coming up March 1.

clare.malone: I will point out here, just to be the fact-checker that I once was, that Ted Cruz is actually the only candidate who has stopped Trump thus far. Don’t count him out, Harry.

natesilver: Yeah, it’s a bit of a mystery to me why Cruz’s numbers have been so flat.

harry: Cruz’s numbers are flat because he comes off as a jerk.

natesilver: SHOW ME DATA ON THAT HARRY

harry: I mean, we’ve argued this over and over again. His colleagues for the most part hate him. He’s gotten zero — count ’em — ZERO endorsements from fellow senators. Heck, tea party hero Mike Lee won’t even endorse him. Meanwhile, you have Ben Carson basically calling him a liar on stage. And I can say that in person, Cruz was funny and personable. But he clearly rubs people the wrong way.

clare.malone: The Wild Berry Skittles that several people in this room have ingested in the past 20 minutes seem to have some fire baked in. (Note: Skittles probably not baked.)

natesilver: Cruz needs to beat his polls in South Carolina and at least draw it to a photo finish with Trump. Which is not totally out of the question — we all remember what happened in Iowa, and some of the private polls show Cruz and Trump closer to each other than the public ones do.

If Trump beats Cruz by 15 points in what should be a pretty good state for Cruz, it seems safer to say that Cruz has limited upside. Cruz will win a bunch of delegates in Texas and probably win several primaries and caucuses in the Mountain West. But that’s not enough to have a path to the nomination.

clare.malone: He’s probably not going to win, but he may be a spoiler for a long time in this race.

micah: That seems like the key question for Rubio, Clare, right? How long does Cruz stay around?

natesilver: Yeah, it could make Cruz a power broker of sorts. Suppose Cruz stays with the race for a long time and we go into the convention with Trump having 40 percent of delegates, Rubio 30 percent, Cruz 20 percent, and the other 10 percent is other candidates or unpledged delegates. How does that knot get untied?

clare.malone: Cruz wants to stay in for all the Southern states to vote for sure. He’s here for the discernible future.

micah: CONTESTED CONVENTION!

clare.malone: IN CLEVELAND! The greatest city in the world.

natesilver: All right, let’s do one more sanity check. As I type this, Trump has a 46 percent chance of winning the nomination, according to Betfair. Buy, sell, or hold?

harry: I’m still selling this, but I’d have to be the dumbest or most stubborn person alive to think his chances haven’t risen SIGNIFICANTLY.

natesilver: I’m holding. Putting Trump’s chances at somewhere around 45 percent to 50 percent seems reasonable. There are reasons to be skeptical of how high Trump’s ceiling is. That’s been a big part of the reason for our skepticism about Trump from the beginning, really. But he’s ahead in basically every poll in basically every state. Ordinarily, you’d expect a candidate like that to be priced quite a bit higher than 45 percent to 50 percent, so there’s already a pretty steep discount built in.

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