Editor’s Note: Hugh Hewitt is a lawyer, law professor, author and host of a nationally syndicated radio show. He served in the Reagan administration in posts including assistant counsel in the White House and special assistant to two attorneys general. The opinions expressed in this commentary are his.

Story highlights

Hugh Hewitt: GOP primary electorate may favor Donald Trump over everyone else, but not over field as a whole. Has he hit his ceiling?

If so, he says, the GOP convention in July could end up in an 'open convention,' and could be bad news for Hillary Clinton

CNN  — 

National polls are valuable glimpses of where an electorate is on any given day, and right now the GOP primary electorate favors Donald Trump by a lot over everyone else.

But not over the field as a whole. And therein lies the question: Has he hit his ceiling? If so, the Cleveland convention will be the most interesting in more than a century.

Before we dive deep into preparation for Tuesday’s Republican presidential debate on CNN, let’s review the numbers and look ahead.

- Source: CNN " data-fave-thumbnails="{"big": { "uri": "https://media.cnn.com/api/v1/images/stellar/prod/151209230138-donald-trump-lemon-intv-bts-ctn-00022901.jpg?q=x_229,y_59,h_682,w_1212,c_crop/h_540,w_960" }, "small": { "uri": "https://media.cnn.com/api/v1/images/stellar/prod/151209230138-donald-trump-lemon-intv-bts-ctn-00022901.jpg?q=x_229,y_59,h_682,w_1212,c_crop/h_540,w_960" } }" data-vr-video="false" data-show-html=" The Lead " data-byline-html="
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New poll shows Trump holds double-digit lead
02:23 - Source: CNN

It requires 1,236 “yes” votes from delegates to win the GOP nomination in Cleveland in July. Right now, under the Republican National Committee’s “Rule 40,” it also requires a candidate to have won at least eight state contests to have his or her name entered into the nomination process. (This rule will almost certainly be changed if no candidate has the necessary 1,236 delegates before the convention is gaveled to order.)

The February contests in Iowa, New Hampshire, South Carolina and Nevada put 30, 23, 50 and 30 delegates up for grabs respectively, and those 133 delegates will be awarded proportionally — that is, the number of delegates each candidate receives in a primary or caucus is proportional to the percentage of the vote they received.

On March 1 (Super Duper Tuesday), a host of states hold their primaries and 565 delegates are at stake that night. As with the February contests, these delegates will be awarded proportionally.

Another approximately 300 delegates are available for the winning in various venues and in various dates between March 2 and March 14, again with delegates allocated proportionally.

- Source: CNN " data-fave-thumbnails="{"big": { "uri": "https://media.cnn.com/api/v1/images/stellar/prod/151209061632-donald-trump.jpg?q=x_0,y_923,h_1617,w_2873,c_crop/h_540,w_960" }, "small": { "uri": "https://media.cnn.com/api/v1/images/stellar/prod/151209061632-donald-trump.jpg?q=x_0,y_923,h_1617,w_2873,c_crop/h_540,w_960" } }" data-vr-video="false" data-show-html=" The Lead " data-byline-html="
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MT. PLEASANT, SC - DECEMBER 7: (EDITORS NOTE: Retransmission with alternate crop.)  Republican presidential candidate Donald Trump speaks to the crowd at a Pearl Harbor Day Rally at the U.S.S. Yorktown December 7, 2015 in Mt. Pleasant, South Carolina. The South Carolina Republican primary is scheduled for February 20, 2016. (Photo by Sean Rayford/Getty Images)
Democratic consultant: we're "giddy" over Trump candidacy
05:24 - Source: CNN

Thus before the Super Tuesday of March 15, the first date on which states can give all their delegates in one swooping “winner take all” allocation, regardless of winning with only a plurality, a total of about 1,000 delegates will have been sorted out and committed, at least for the first ballot in Cleveland, to the dozen GOP candidates.

If, for example, Donald Trump’s recent polling numbers are correct (though they could be greatly understated or overstated, as we saw in last month’s Kentucky governor’s race when Republican Matt Bevin was supposed to lose by at least 4 points but won by 9), Trump will pick up 35% of these 1,000 delegates available before March 15, or about 350 of the 1,236 needed to achieve the nomination.

That’s a fine chunk of delegates but nowhere near the number he needs to win the nomination.

No candidate, in fact, seems remotely close to a scenario in which he or she wins the necessary 1,236 delegates, and thus the fabled “open convention” may be upon us.

I call the “open convention” the unicorn of American politics. Political consultant Rick Wilson goes further, calling it a “buck naked leprechaun riding on a unicorn,” which conveys even more spectacularly how unprepared American media is for such an event. Every delegate a player, and a Twitter account to find and follow.

Those are the numbers. That is the likeliest scenario: An open convention. Far from a dwindling field, watch to see if it expands as the old, old practice of “favorite son” candidates looking for leverage in Cleveland may make a return.

An interesting convention in Cleveland will be very bad news for the boring, stale and widely distrusted Hillary Clinton, who lacks a clear target to carpet bomb and any energy in her ranks, much less the ability to generate enthusiasm for the worst rebranding campaign in modern American political history.

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