So that’s why Cruz won’t give a straight answer when he’s asked if he’ll break his pledge over Trump insulting his wife. It’s not about proving he’s a “man of his word.” It’s because, as usual, he’s well-versed in the rules and Trump isn’t.

Hard to overstate what a big deal this would be if the challenge prevailed and Trump lost these delegates. By winning statewide and in every congressional district, Trump turned South Carolina into his fourth-biggest delegate haul of the campaign to date. He netted 50 there. If he lost those, his odds of getting to 1,237 on the first ballot would suddenly grow much more difficult, maybe prohibitively so. I wonder if Team Cruz and their loyalists in the SC delegation are really going to press this or if it’s just a way to needle Trump for being an idiot in undermining the pledge.

The Palmetto State was one of several that required candidates to pledge their loyalty to the party’s eventual nominee in order to secure a slot on the primary ballot. Though Trump won all of the state’s delegates in the Feb. 20 primary, anti-Trump forces are plotting to contest their binding to Trump because of his threat on the pledge Tuesday…

South Carolina Republican Party Chairman Matt Moore gave credence to the anti-Trump claims.

“Breaking South Carolina’s presidential primary ballot pledge raises some unanswered legal questions that no one person can answer,” he told TIME. “However, a court or national convention Committee on Contests could resolve them. It could put delegates in jeopardy.”…

Those delegates would be bound to Trump on the first ballot according to state and RNC rules. The challenge, which could only be filed once delegates are selected, would seek to allow them to be free-agents on the first ballot, thereby keeping Trump further from the key 1,237 figure he needs to secure the nomination.

If you missed what he told Anderson Cooper on Tuesday night, watch below. Here’s the filing form Trump had to sign last year to qualify for the South Carolina primary. The top half is the statement of intention to seek the state party’s nomination for president and the bottom half is the pledge: “I hereby affirm that I generally believe in and intend to support the nominees and platform of the Republican Party in the November 8, 2016 general election.” Hmmm!

A secondary question is what would happen to the delegates if Trump was held to have violated the registration requirements by breaking his pledge. One possibility is that they all become unbound free agents, which would undoubtedly mean heavy defections to Cruz but would at least leave open the possibility that Trump could persuade some to stick with him. Another possibility, though, is that the delegates would then become bound to the second-place finisher in the primary — which was Marco Rubio, not Ted Cruz. Rule 11(b) of the South Carolina GOP’s nomination rules awards the state’s delegates to the second-place finisher in the state if the first-place finisher, for whatever reason, isn’t nominated at the convention. Trump will be nominated, but if he’s ruled ineligible for breaking the pledge, the South Carolina GOP could follow this rule as guidance and award his delegates to Rubio on the first ballot instead. Which, ironically, would be a worse outcome for Trump than if they were simply unbound and left to choose between Trump and Cruz. Remember, Rubio has been writing to state Republican officials to say that he wants his delegates to remain bound to him at the convention, precisely because he doesn’t want to let Trump have any chance of winning them over on the first vote. If South Carolina’s 50 are handed to Rubio, all 50 are gone for Trump’s purposes. And since the first ballot is effectively the only one he has a realistic chance of winning, that means they’re gone for good.

Two obvious questions for the convention Committee on Contests (or a court, which is where this would almost certainly end up). One: What does it mean to break this pledge? If Trump says tomorrow, “I changed my mind again and will support the nominee,” does that mean his 50 delegates are re-bound to him or is this a “once you’ve broken the pledge you can’t un-break it” sort of thing? Can he break it by saying the wrong thing in an interview or would he have to sign something affirming his intention to break it? The idea here, I assume, is that he committed fraud in running in the Republican primary when he had no intention of honoring the pledge — but what if he really did intend to honor it at the time? How is that fraud? Two: Where does it say that violating the pledge, if Trump violated it, will be punished with a loss of delegates? The party could sanction him in some other way, like with a censure. On the other hand, why should a court interfere with a private political party dispensing punishments for breaking its rules as it sees fit?

I assume Cruz is interested in pursuing this or else it wouldn’t have been leaked by his allies to Time. I’m also inclined to believe this is correct: “A Committee on Contests willing to unbind Trump’s South Carolina delegates is a Committee on Contests willing to do a lot of other things.” If the rules-makers at the convention want to stop Trump, they’ll find a way. If it isn’t this, it’ll be something else.

Update: The chairman of the SC GOP tries to quell a growing uproar: