9 p.m. ET on Fox Business. That headline is sexy but it’s probably false: If anything, this is the “everybody punches Marco Rubio in the face” debate. Jeb certainly will, as that’s the only reason his campaign still exists at this point. Chris Christie will, hoping that a hard hit will finally clear his path in New Hampshire. Cruz will, since he still fears a head-to-head race with Rubio above others. Trump probably will too, just because he’s Trump. Heck, by the time the evening’s over, there’s a 50/50 chance that Ben Carson will awaken from his slumber and call Rubio a RINO. It’s bound to be hours of fun for Trump fans and Cruz fans alike.

Unless, that is, Trump and Cruz start swinging at each other. Politico seems convinced that Cruz is at long last ready to engage but I’ll believe it when I see it. What’s changed lately that would make Cruz rethink his long-held strategy of ingratiating himself to Trump fans? Remember this data set from the Cruz/Snowden post?

Fully 75 percent find it very or mostly attractive that Cruz has held his fire on Trump. I think Cruz is prepared to counterpunch tonight, especially if Trump comes after him over his “natural-born” status, but he won’t initiate hostilities. Meanwhile, Trump has an odd tendency to avoid conflict at debates. Remember, he also attacked Cruz in the week before the last debate, calling him a “maniac” for how he’s clashed with Senate Republicans. Face to face with Cruz onstage a few days later, he turned into a pussycat, saying he felt reassured that Cruz has a “wonderful” temperament. Maybe, after all the hype this week about “New York values” and natural-born Canadians, war is unavoidable. It probably is now that we’re less than three weeks out from the caucuses and it’s dawning on Trump that there’s no reason for him not to attack Cruz. But who knows? We’ve all seen how weirdly chummy Trump gets with the other candidates at these things. Why risk a war of words with Cruz on national television that he might lose when he could gladhand him tonight and then accuse him of being a trojan horse sent by Ottawa tomorrow?

Speaking of Cruz’s status, Reince Priebus finally dares to go where Marco Rubio, Mitt Romney, Debbie Wasserman Schultz, and nearly every legal scholar who’s looked at the eligibility issue have already gone:

https://twitter.com/amandacarpenter/status/687750554567614464

I wonder if that news will trickle down to Trump in time for him to grouse tonight about the RNC meddling in the primary to help Cruz win (giggle). That’d be a fine, hallucinatory start to the long-delayed Trump/Cruz war — each man will accuse the other of being a tool of the establishment, Trump attacking Cruz for his Washington connections and fancy Goldman Sachs loans and Cruz attacking Trump for his palm-greasing, center-left fatcat “New York values.”

Whatever happens, I’ll be shocked if the needle moves much in Iowa over the next week because of this. (The week after, as late-deciders finally make up their minds, might be different.) If anything shakes loose, I assume it’ll be in New Hampshire depending upon how Rubio fares against Bush and Christie tonight. Pundits are forever heralding magical “Rubio moments” at these debates, writes Michael Brendan Dougherty, only to see Rubio stagger along at 12-15 percent in poll after poll in the following weeks. Is tonight the night that changes or is it 15 percent all the way down for the great establishment hope?

Rubio has the sympathetic coverage and interest of the Beltway media. He has basked in open cheering from influential conservative outlets like National Review Online and The Weekly Standard. He’s collecting endorsements from conservative congressmen. He and his allies have spent an enormous amount of money — second only to pro-Jeb Bush groups — trying to blunt the rise of Chris Christie, John Kasich, and Ted Cruz. And yet every poll for months in the first two nominating contents has him between 10 and 14 percent. He’s had 15 moments in the media over the past three months. And 15 weeks of same in the polls…

And definitely don’t pay attention to the fact that Marco Rubio’s fans, who had spent many golden Rubio-moments exulting in their man’s triumph over his former mentor, are now whining to the press about the funny ads coming from Right to Rise, a Jeb Bush-aligned Super PAC…

The whole premise of Rubio’s candidacy is that his fresh face and new way of thinking are guaranteed to beat stale legacy candidates like Hillary Clinton. And yet, he needs to be protected from Bush.

We’re still a ways away from “Rubio can’t win” but I think we’ve reached the point where we can rule out vast swaths of Republican voters suddenly realizing that he’s the perfect man for the moment, a sort of electoral epiphany that some Rubio fans seem convinced will be upon us at any moment. If he wins now, it’ll look more like how Romney won, with a modest base of enthusiastic supporters paired with a much larger group of Republicans who’ve concluded that the other candidates are too kooky or unlikable for them to support. It’ll be less “Rubiomania” than “Anybody but Trump and Cruz.”

Gotta get past Christie first, though. As we wait for the show to start, here’s George Will hammering Rubio for his poor judgment, from the Gang of Eight to intervention in Libya to supporting Obama’s horrible Star Chamber standards of due process for campus sexual assaults. Rich Lowry thinks Rubio’s electoral problem may be simpler than that: He’s very much not a perfect man for the moment given that the moment is defined by populist anger and Rubio is perpetually sunny and soft-spoken. There’s something to that, but one thing I’ve heard from Rubio critics on the right repeatedly is that if he had steered cleared of the Gang of Eight and had run this year with his conservative credentials still as firmly intact as Cruz’s are, he’d be crushing the field. In a straight-up personality contest between Rubio and Cruz, Rubio wins handily — even with the public as sour as it is. (Whether Rubio would be in a financial position to run this year absent his connection to the Gang of Eight, which was his big “in” with the donor class, is a another matter.)

In lieu of an exit question, I’ll leave you with new poll data from WSJ/NBC: Trump 33, Cruz 20, Rubio 13. That’s a six-point gain by Trump since the last WSJ/NBC poll and a two-point drop for both Cruz and Rubio. Trump seems to be gaining momentum, not losing it, as voting approaches. (What happened to the big mega-donor effort to blow up Trump with attack ads?) The good news for Trump critics is that Cruz leads him head-to-head, 51/43. The bad news is that Trump leads Rubio head-to-head, 52/45. The number of Republicans who said they could see themselves voting for Trump was 23 percent in March of last year. Today: 65 percent. Cruz might be the last hope of stopping this train before it builds up steam.