Hogan Gidley, who served as national communications director for Mike Huckabee’s presidential campaign, appeared on Wednesday’s edition of Breitbart News Daily with SiriusXM host Stephen K. Bannon to discuss a crucial aspect of the Republican primary: the previously obscure, but increasingly notorious, Rule 40.

Technically, most of the analysts citing Rule 40 are referring to the current version of Rule 40(b), which sets a certain minimum threshold for candidates at the Republican National Convention. According to this rule, candidates must arrive at the convention with a majority of the delegates from eight states or territories, or else they are disqualified from the first round. In most elections, this is a mere formality because the clear winner of the nomination is well-known before the convention begins, making the convention an extended infomercial for the party and its nominee.

Of course, there is good reason to suspect the Republican convention will be rather more exciting this year. Gidley noted there is apprehension among front-runner Donald Trump’s supporters that the GOP Establishment will use some “shenanigans” to “steal” the nomination from him at the convention. Among those shenanigans could be changing Rule 40 to bring candidates who don’t meet the established minimum threshold into the game.

There are two ghosts from the 2012 election haunting the Shakespearean drama of the 2016 primary, and Gidley invoked them both in a single breath: Ron Paul and Mitt Romney.

“This is actually called the ‘Ron Paul Rule.’ The Romney people put this in place,” Gidley explained. “The Establishment hurt Ron Paul, but I think this Establishment rule will actually help Donald Trump.”

Gidley noted there is no way for one of the last three remaining candidates, Governor John Kasich of Ohio, to win the necessary majority of delegates from eight states. Texas Senator Ted Cruz currently stands at seven.

He further asserted that, contrary to much speculation from pundits, Rule 40(b) technically blocks disqualified candidates from participating in any of the subsequent ballots, which scuttles the notion of denying Trump victory in an initial vote where only he and Cruz are qualified candidates, and then parachuting some other Establishment-preferred candidate into the convention hall to seize the nomination, possibly someone who didn’t even run in the 2016 primary at all.

(Cruz is arguably even less acceptable to the Establishment of his own party than Trump — a point that will be made by many an anguished Hamlet delivering monologues over the skull of Marco Yorick in the weeks ahead, to continue that Shakespeare metaphor.)

Rule 40 “was an effort to stop the Ron Paul faction from gaining traction at the convention,” Gidley recalled. “And now we see the fruits of that rule, which was designed to stop Ron Paul, could effectively stop the Establishment.”

“The second part of the rule is, you can’t even count votes for anybody else who doesn’t meet that threshold,” he pointed out. “So people can try to submit votes for other people — like Kasich, or like Rubio, or like Romney — but if you haven’t won a majority of the delegates in eight states, you can’t be on any ballot, at any time. First, second, third, fourth, fifth — it doesn’t matter.”

It has been suggested that the Rules Committee will simply change Rule 40 to arrange whatever outcome is necessary to block Trump, but Gidley was skeptical of this idea. Normally, a presumptive candidate who has reached the “magic number” of bound delegates needed to secure the nomination can control the rules. If Trump is held below that 1,237-delegate threshold this year, the Rules Committee could theoretically rewrite the rules to hurt him, but Gidley anticipated sheer chaos if such tactics were employed.

“If you think people are mad now … it’s gonna be a political jihad,” he warned.

Breitbart News Daily airs on SiriusXM Patriot Channel 125 weekdays from 6:00AM to 9:00AM EST.

You can listen to the full interview with Hogan Gidley below: