Last time I did a thread like this, on the day of the New Hampshire primary, I gave you nine carefully reasoned paragraphs on why Trump would be held to 26 percent and Rubio would finish a strong-ish third behind Kasich. Insert your own fart noise here as a salute to that. Today it’s all about gut instinct, for the simple reason that so many large variables have been introduced into the race since last Saturday that anything from a Trump mega-blowout to a surprise Cruz win to a shocking Rubio win seems vaguely possible. Over the past seven days we’ve had Trump accusing George W. Bush of lying about WMDs in Iraq and telling a big TV audience on CNN that he “likes” the ObamaCare mandate, a statement which he’s since tried to walk back. We’ve had Cruz and his allies going kitchen-sink on Trump as a threat to southern and evangelical values on everything from gay marriage to abortion to the Confederate flag; we’ve also had Trump accusing Cruz of being one of the sleaziest liars he’s ever known and threatening to sue him for defamation. And of course we’ve had Rubio landing Nikki Haley’s endorsement and barnstorming the state with her, Tim Scott, and Trey Gowdy, successfully enough that he’s now actually slightly ahead of Cruz for second place in RCP’s poll average. That’s a lot of heavy ammunition detonating on all sides. Who gets blown up tonight and who walks away safe?

I’m confident that Trump wins easily, just because he’s led so comfortably for so long in so many polls that you’d be a sucker to bet against him. It’s true that several state polls this past week have him below 30 percent, but it’s also true that his average remains well north of 31, 13 points ahead of the new second-place Rubio. In fact, for all the hype about that WSJ/NBC national poll that was released this week showing Cruz ahead of him by two points, Trump has trailed in South Carolina only once since the beginning of July 2015. That came in November, when Ben Carson nosed ahead of him by a single point. Every other poll taken in SC over the past seven and a half months has Trump ahead, and the great majority have him ahead by double digits. (Of the last nine taken, Trump leads by 10 or more points in seven.) FiveThirtyEight currently has him as a 76 percent favorite to win, with Cruz and Rubio each stuck at 11 percent. I’m not gutsy enough to go against that grain. The harder question tonight is guessing how Cruz and Rubio will do, especially in light of Rubio’s poll movement since Haley hopped aboard. The Rubio surge does appear to be real, as noted above, and not just according to scientific polls. Data nerds like to keep an eye on local Google trends on primary day as a rough gauge of whom undecideds might be interested in. Here’s what that graph looked like this morning:

Latest Google Trends out of SC: pic.twitter.com/qdBkkc3IQm

— Patrick Ruffini (@PatrickRuffini) February 20, 2016

So why do I think Cruz will hold off Rubio for a (distant) second? Really for no better reason than that Cruz appears to have the best ground game in the field and that Rubio, unlike Cruz, continues to have competition within his own “lane.” If Jeb had quit after NH, Marco would be a no-brainer to finish second tonight and Cruz’s strategy would be on life support. As it is, I think Bush may get just enough help from Dubya — and maybe even some sympathy given that his campaign’s on death watch — to pull a few points away from Rubio. But that’s pure hunch. It’s quite possible that the opposite will happen, with some chunk of Bush and Kasich supporters deciding to jump ship to Rubio at the last second because their preferred candidate has zero chance of winning. Then again, it’s also possible that a chunk of Carson supporters will decide that he’s a lost cause too and they’ll split for Cruz — or Trump. It feels strange to say even though it’s basic math but how the also-rans fare tonight will determine the course of the race going forward. If Bush’s, Kasich’s, and Carson’s fans abandon their candidates because they’re now convinced this is a three-way race and the field needs winnowing then the margins between the top three will be tighter than anyone expects.

Incidentally, if I’m right about how this shakes out, it’ll be a total disaster for anti-Trumpers. Cruz finishing 10 points behind Trump in a southern evangelical stronghold would start the early death watch for his campaign, with a last stand set for the SEC primary on March 1st. Rubio finishing third again despite the push he’s gotten from Haley, Scott, and Gowdy would send his campaign into advanced death watch, with Rubio desperately needing an encouraging showing in Nevada or in the SEC. If things don’t turn around very quickly, Trump could effectively wrap up the nomination 10 days from now. Cheers!