Must Republicans choose between Trump or chaos?

New York surrendered utterly to Donald Trump and you'd think that might leave him with nothing to grumble about.

But no, even after the biggest of his primary wins he still would not allow his gripes the night off.

"It's a crooked system, it's a system that's rigged," he said in victory. "No one can take an election away, with the way they're doing it in the Republican Party."

What on earth was he talking about, you might wonder.

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We've grown accustomed to Trump moaning about unfairness when he loses. It's part of the "Trump being Trump" routine.

He often grouses about "rigged" or "stolen" votes when things don't go right for him. That's his way. He did it after Iowa, Colorado and Wyoming. He even admits, "I only complain about the ones where we have difficulty."

But this was different, and not just because it followed a winning night.

It shines a light on how things could unfold for the Republicans when they get to their convention in Cleveland in July.

You can decide for yourself whether it means the system is rigged and crooked, but here's why Trump said what he said:

The Trump team has absorbed some shocking upsets lately that have forced it to dive deeper into the inky pit of rules that govern the nominating race and they're finding out it's a pretty crazy place down there.

Delegate slots not same as delegates

Consider what happened in the Peach State, Georgia.

Trump won the Georgia primary on the first day of March, Super Tuesday. He got 39 per cent of the vote and 42 delegates, so end of story, right?

Sorry. What really happened was that Trump got 39 per cent of the vote and 42 delegate slots. Just the slots, not the delegates.

There was another round of voting at the county level in Georgia this past weekend to fill those delegate slots that Trump won, and guess what? A number of the Trump slots went to Ted Cruz supporters instead. Others still went to John Kasich's people.

All those delegates will vote for Trump on the first ballot, but otherwise they'll vote for Kasich or Cruz if they get the chance. They'll also vote on the rules that will govern the convention, which might not help Trump either.

But it's all fair and square. In fact, it's the way delegates have been chosen for decades.

In the past, though, it didn't matter so much. It was never that important who the delegates were because they weren't going to choose the nominee at the national convention. They were only going to ratify a choice that had been engineered by the party establishment.

That's obviously not the case this time.

There's a real fight for the nomination and when Trump said, "nobody should take delegates and claim victory unless they get those delegates with voters and voting," he meant delegates like those selected in Georgia on Saturday.

Call them Trump SINOs - Supporters In Name Only.

SINO is a term coined by John Patrick Yob, a Republican operative who's worked for Senators John McCain, Rick Santorum and Rand Paul.

He's written a book called, prophetically, CHAOS, The Outsiders Guide to a Contested Republican National Convention, 2016.

Unbound delegates

Yob has been watching the Republican Party disintegrate since about 2010 when the Tea Party wave crashed down on it and then rolled on into Congress.

He anticipated that the Tea Party would soon mount a presidential campaign for a Sarah Palin-like candidate. He figured that would so destabilize the Republican Party that a contested convention would be inevitable.

(He's not saddened by this, incidentally.)

Yob began to think about the mechanics of how the campaign would unfold and to imagine what the nominating convention would look like. He imagined it would look like chaos.

He didn't add a self-funding celebrity billionaire populist into the mix at first, but, as he writes, that just "adds to the chaos."

His book went to the printer days before the South Carolina primary in February.

It unpacks the rules of the caucuses, primaries and conventions and, ominously, finds that in some of the most important areas whether delegates are truly "bound" to vote for a candidate, for instance there really are no clear rules.

Chaos is what it claims to be: A good guidebook to how and why the 2016 nomination campaign unraveled and where all the unraveling will lead.

Reading it you might think that if any of the candidates understands what Yob understands it's probably Ted Cruz.

Trump would realize that too, now.

He denies that he's been outplayed in the campaign ground game, but there's no doubt that's what's happened.

Cruz has trumped Trump by knowing the rules better and working them harder.

Trump has brought in a new campaign manager to shore up his ground game, but it might already be too late.

He could still gather what he needs to win a majority on the first ballot.

But if not, we've been warned.

"The people aren't going to stand for it", says Trump, and the ever-more likely alternative is the mayhem of a chaotic convention.