Forget Trump. Paul Ryan is the likely GOP nominee

The Wisconsin primary could very well undo Trump's lock on the Republican nomination. Senator Ted Cruz defeated Trump in the Badger State, which will make it nearly impossible for the New York billionaire to enter the GOP convention in Cleveland with the 1,237 delegates he needs for the nomination — or even get within 100 delegates to the magic number.

But here's the catch: That doesn't mean Cruz will be the nominee.

In fact, the closer Cruz comes to catching up with Trump without actually overtaking him in the delegate count, the more likely Cruz will be denied the nomination, too, in a truly brokered convention.

Here's why:

First, a truly brokered — or open — convention is not really what's happening when you have one candidate very close to the needed delegate count with several others very much behind. That's simply a situation where a few deals need to be made to bring about an inevitable coronation. The best example of a convention like that was the 1976 Republican confab, where President Ford was able to use an appeal for party unity to win Ronald Reagan's support and secure the nomination. It helped that Ford had a clear lead and there was never enough rancor between the two candidates to make joining forces impossible.

Speaker of the House Paul Ryan (R-WI).
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Speaker of the House Paul Ryan (R-WI).

A really open convention occurs when you have two candidates who are very close in the delegate count, (roughly 100-150 apart), who are also irreconcilable camps who will never agree to support one another. Things then become "open" when it becomes clear to the delegates that a compromise candidate has to be found that both sides can at least begrudgingly support. We haven't really seen a truly brokered GOP convention since 1920, when the Republicans settled on Ohio Senator Warren Harding as the nominee. Harding entered the convention a distant fourth in the delegate race. But when whisker close frontrunners Gen. Leonard Wood and Illinois Governor Frank Lowden couldn't agree to support one another, their delegates settled on Harding after 10 dramatic ballots. Harding went on to a resounding victory in November.

The lesson here is that truly brokered conventions have three key elements: two very close front-runners, irreconcilable camps, and an eventual compromise nominee. Anything that doesn't have those three elements is not really a brokered convention.

Wisconsin can make a 1920-like scenario possible because it has the power to bring Cruz much closer, but not over the top. After Wisconsin, Trump has 743 delegates, Cruz has 517 and Kasich has 143, according to the AP. The Wisconsin win provided Cruz with some momentum but not enough to overtake Trump — there's little chance Cruz can win under any circumstances in the upcoming primaries in New York, New Jersey, and probably West Virginia.

Another key for Cruz are the undeclared delegates, some estimate there will be as many as 135 heading into the convention. Cruz will need to get about 90-100 of them to stay within viable striking distance of Trump.

But even if an almost best-case scenario shakes out for Cruz, this is a suicide mission whether he realizes it or not. Because a brokered convention needs two — not just one — sacrificial lambs. Coming within 100-150 delegates of Trump will do a lot to convince any remaining delegates not that Cruz is the answer but that Trump really doesn't have any chance of getting enough Republican support to even remotely challenge Hillary Clinton in the general election.

The fact that Trump has now lost to Clinton in more than two dozen polls is the real reason why Cruz is seeing a new uptick in support anyway. It's important to understand that, because Cruz's real value to the party's chances to win the White House comes from being able to take down Trump. That's it.

So that leaves the question: Who steps in as that compromise candidate when the Trump and Cruz delegates realize they will never win each other over? Before you jump on the "historical coincidence train" and conclude that Ohio's John Kasich will take his fellow Ohioan Harding's road to the nomination, look at some of the facts on the ground. Kasich hasn't shown much of a real national effort to win the nomination so far. It's true he doesn't have the money that Cruz does or the free national media coverage Trump enjoys, but that doesn't explain the lack of the kind of full court press Kasich is still long overdue to deliver. He's also not projected to win any more primaries at all.

And probably worst of all, the Trump and Cruz campaigns are becoming more and more hostile to Kasich and demanding he drop out of the race. Kasich has avoided the nastiness that's overshadowed the GOP race so far, but that's ending now.

More and more, it's apparent a Republican leader who never was a candidate for president would have to be the compromise nominee if we do get a truly brokered convention. And despite all his protestations, House Speaker Paul Ryan would be the most likely choice in that kind of scenario. I'm not saying Ryan would necessarily be the best candidate, but he's already been called upon to save the party once and it's likely he would be again for a number of reasons. His experience as the vice presidential nominee four years ago means he will have at least a few people close to him experienced in national campaigning.

The fact that Ryan has not really attacked Trump or Cruz so far in this mean season will make him much more palatable to both camps' delegates. He even wisely stayed out of the country while his home state of Wisconsin held its crucial primary, (he voted absentee). And most importantly, he's not named "Cruz" or "Trump."

Ryan's chances of winning are a different discussion, as is the crucial decision of who would be his running mate. But in any case the current Speaker of the House stands a much better chance than Trump, who cannot beat Clinton, and Cruz, who cannot win the nomination.

Commentary by Jake Novak, supervising producer of "Power Lunch." Follow him on Twitter @jakejakeny.

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