Ed’s live on the scene in Vegas so he’ll be handling open-thread duties later. I want to chip in my prediction, though, about where the fireworks are likely to happen. Lots of people on social media seem to think tonight is when the Trump/Cruz war finally goes nuclear. I’m skeptical. It’s within the moderators’ power to force a confrontation by asking Trump or Cruz about Trump’s “maniac” comments on Sunday, but Cruz has showed he wants no part of a fight and Trump tends to be (curiously) restrained at debates. Plus, Trump might not want to press his luck with grassroots righties by hitting Cruz again after yesterday’s shot across the bow from Rush Limbaugh and Mark Levin.

If Trump is asked about what he said, and he probably will be, he’ll politely reiterate the point that President Cruz will have trouble working with Congress but he’ll also water it down by emphasizing how much he likes Cruz. (One sly way to diminish Cruz without insulting him is to continue to remind people how eager Cruz seems to be to defend Trump on everything.) And Cruz will repay the compliment and say something like, “Donald and I aren’t enemies. Our only enemy is the Washington cartel.” Fin. That’s how I’d bet. Trump tends to do his sniping on Twitter and at rallies, when the target isn’t in front of his face — which is ironic given that that was his initial grumble about Cruz questioning his judgment privately, at a fundraiser, instead of where Trump could hear him.

But don’t worry. If the Trump/Cruz war tonight is a dud, there should be other wars to keep you entertained. I agree with Ross Douthat entirely — or almost entirely:

If one of the center-right candidates beats Rubio in New Hampshire outright, then they would have a claim on the establishment “lane,” a claim to media attention, an argument that the race is really a four-man contest or even that they, not Rubio, belong in the final three. And right now, based on how the campaign has gone to date, on buzz and strategy and polling, it feels like Christie is the only one of the center-right scrum who has a real chance of being that Rubio-slaying or at least Rubio-wounding guy.

So that means the New Jersey governor needs a clear case, in the remaining debates, for why Republican voters should prefer him to Rubio — because come New Hampshire he’ll need a small chunk of Rubio’s committed supporters and a larger chunk of the voters who might otherwise break Rubio’s way. Part of that case is obvious enough: He’ll offer tough-guy affect, 9/11 references and boasts about his executive experience (just don’t look too closely at New Jersey). But the rest presents an interesting dilemma.

Right. Christie’s going to swing hard at Rubio, the only guy who’s still in front of him in the center-right “lane” in New Hampshire. In fact, he’s already starting swinging. Here’s what he said in an interview a few weeks ago with Jeffrey Goldberg:

Christie: I have to win some more than that. It won’t happen quickly. But if it’s not me, who’s it going to be?

Goldberg: Hillary Clinton? Marco Rubio? Ted Cruz?

Christie: Why Marco Rubio? I’m fascinated by this.

Goldberg: He’s a very smart, articulate young guy, great personal story—

Christie: —I didn’t ask you to give me what you read in the Times.

Goldberg: He’s very smart. I’ve talked to him. Very likable.

Christie: There’s not a lot of depth there.

A few days before that, he dismissed Rubio as “a first-term senator who’s never had to make any significant decisions in his career.” This week he went after Rubio for not campaigning hard enough in New Hampshire. Christie’s problem is that he and Rubio aren’t far apart on the showiest elements of Rubio’s agenda, namely, interventionism abroad and comprehensive immigration reform. That’s why he’s taken to hitting him on intangibles like “depth” and inexperience and work ethic rather than on policy. You’ll hear all of that tonight. Douthat thinks Christie’s facing a dilemma, though: Since he and Rubio are both competing for center-right votes, in theory the further right Christie goes to attack him, the more Christie might end up alienating centrists who like the moderate notes in Rubio’s platform. If you’re a Jeb Bush fan thinking of backing Rubio, why would Christie attacking Rubio as a sellout on amnesty make you more likely to support Christie? Point taken, but if you’re a Jeb Bush fan, your main worry right now isn’t “Rubio or Christie?”, it’s “MY GOD THE RACE MIGHT COME DOWN TO TRUMP AND CRUZ.” Once you reach that stage of panic, you’ll enthusiastically back any center-righty who can win, regardless of what he did to make those wins possible. If Christie continues to charm his way towards the lead in NH and looks like he’d hit Trump and Cruz harder than Rubio would as one of the final three, I think plenty of center-right late deciders will back him even if they disagree with some of his attacks on Rubio. Besides, is anyone under the impression that Christie’s a true blue right-winger? The donor class knows who he is and what he believes. He’ll revert to centrist form if/when he’s elected president.

That’s one war. The other war will be between Cruz and Rubio, with Cruz likely to be the aggressor for two reasons. One is that Rubio’s working hard to paint him as some sort of Rand Paul twin, to the point where he’s taken to saying lately that Cruz has “isolationist tendencies.” I’m skeptical that that’ll catch on with voters, especially with Cruz straining so hard to counter by talking about “carpet-bombing” ISIS and making sand glow in the dark, but you don’t want to be pigeonholed as weak on national security in a Republican primary. If Cruz comes out swinging in indignation at Rubio’s accusation, he could blow up the impression of him as a dove before it really takes hold. The other reason he’ll come out hard is that he needs to make sure Trump fans don’t start viewing him as gutless for refusing to respond to Trump’s attacks. You and I know that Cruz is ducking Trump for strategic reasons, to stay on the good side of Trump voters in hopes that they’ll back him eventually, but the average Trump fan might not be following the race closely enough to detect the strategy. They might see weakness, just like Jeb Bush showed when he was attacked by Trump, and that’ll be a dealbreaker. One way for Cruz to change that perception is to hit Rubio as hard as he can. Not only will that show “strength” and a willingness to fight, it’ll suggest to Trump fans that he’s capable of hitting Trump hard if he so chose. It’s fine to turn down a fight if spectators are convinced you might win it. That’s not cowardice. That’s alpha-male magnanimity.

How might Rubio respond to all of these attacks? With Christie, I think he’ll go after red-meat stuff — gun control, gladhanding Obama right before election day 2012, etc. The way to stop a candidate with charisma like Christie isn’t to nitpick him on fine policy differences, it’s to hit people in the gut by accusing him of being a phony who’s bad for the party. As for Cruz, Matt Lewis has a few suggestions for Rubio. That task is harder because Rubio obviously risks alienating conservatives if he goes after Cruz for the 2013 shutdown or for attacking the rest of the Senate GOP caucus. (That criticism from Trump is what finally got Limbaugh and Levin after him yesterday.) He’s on safer ground accusing him of being a dove. I wonder if Rubio dares, as Lewis imagines, to call out Cruz for being willing to fight everyone except Trump. And how would Trump react to that? He’s better off siding with Rubio on that than with his “friend” Ted.

Exit question: Remember when Jeb Bush claimed Trump would be in decline by December 15th? Enjoy Jeb tonight, as he’s probably not long for this race.