In arguably the most improbable political season of our lifetimes, this fact has to rank high on the list of things no one could have seen coming. If they gave out report cards for first-term senators, Mr. Cruz would get an "F" in the "plays well with others" category. Party leaders believed that his 2013 gambit to shut down the government over Obamacare was a disaster for everyone but Mr. Cruz, and they have harbored a not-so-secret disdain for him since.
But that's all over — at least for now.
Like Perseus pulling Medusa's head out of a sack to petrify his enemies, Mr. Cruz has been able to dangle the prospect of a President Trump to strike fear in the hearts of even his biggest detractors.
Sen. Lindsey Graham, a South Carolina Republican, once said choosing between Donald Trump and Mr. Cruz was like choosing between being shot or poisoned. Mr. Graham chose his poison. He's out there raising money for Mr. Cruz. Senate Majority Leader Mitch McConnell, a Kentucky Republican whose hatred for Mr. Cruz was the stuff of Sicilian blood feuds, seems to have reconciled himself to the fact that Mr. Cruz is the only person who can stop Mr. Trump. Mr. McConnell's definitely not in love, but he recognizes that these are the cards we've all been dealt.
Team Cruz fears that people such as Mr. McConnell will use the convention in Cleveland this summer to reshuffle the deck and get a new deal — a new candidate more palatable to the establishment. "There is still distrust over whether or not the party is actually willing to accept Cruz as the nominee or if they're using him to shut down Trump only to then stab Cruz in the back come summer," Erick Erickson, a conservative talk show host and Cruz backer, told the Washington Post.
The concern is understandable but overblown. Although a contested convention is likely, the "white knight" scenario, in which someone other than Messrs. Cruz, Trump or John Kasich swoops in and "steals" the nomination, is not.
At an open convention, the delegates, not Republican National Committee Chairman Reince Priebus, are in charge of everything. Imagine if attendees of the great nerd conclave known as Comic-Con set the rules for Comic-Con. Now imagine someone proposed replacing a screening of the new "X-Men" movie with a mandatory daylong seminar on crop rotation in the 14th century. Would it happen?
Yes, it's theoretically possible that the delegates will choose a white knight, but that would only happen after days of deadlocked voting.
In other words, the delegates would have to really want someone other than Mr. Cruz. And given the Cruz campaign's success at lining up huge numbers of sympathetic delegates, that seems unlikely.
Although there is no coherent ideological agenda implied by the term "anti-establishment," it is a recognizable attitude. Messrs. Trump and Cruz have very different philosophies. (For starters, Mr. Cruz has one.) But they are both avatars of the anti-establishment mood, a mood that will be well represented on the convention floor. It seems unlikely that delegates' ultimate choice would be someone so synonymous with the establishment.
The most likely scenario is that should Mr. Trump lose on the first ballot, Mr. Cruz will win on the second or third. In fact, some see a path where Mr. Cruz cobbles together his own delegates, unbound delegates and, say, Marco Rubio's delegates and wins on the first ballot. He's that good at working the system.
There's some irony here, of course. Mr. Cruz spent years building his reputation as the guy who wants to tear down the system, and now it's the system, not necessarily the voters, that may put him over the top.
Nervous Republicans should find this reassuring. Yes, in a normal year, failure to win a majority of votes in the primaries would present a serious PR problem. But this isn't a normal year. Meanwhile, Mr. Cruz is demonstrating, yet again, his ability to do what is required to win. That's a skill set that will be much needed come the fall.
Jonah Goldberg is a fellow at the American Enterprise Institute and editor-at-large of National Review Online. His email is firstname.lastname@example.org. Twitter: @JonahNRO.