A Cruz-Kasich ticket is starting to come into focus with the two campaigns’ joint announcement that they will coordinate on three upcoming primaries. Don’t be so literal as to see things only as coordination in just three states. While many in the press are ridiculing the alliance as too little, too late, and while Donald Trump will sweep five states tomorrow and seem unstoppable, the Texan and the Ohioan are a formidable team, spanning the GOP ideological spectrum and uniting otherwise disparate geography.

Tomorrow, Mr. Trump will win five states, but four are small, and the fifth, Pennsylvania, has a curious system under which most of its delegates (54) are elected directly as unbound and undeclared delegates, many of whom are likely to be Cruz delegates, reflecting the reality that Mr. Cruz has had a ground operation in the Keystone State for months (Mr. Trump hasn’t). In the five states, only 115 bound delegates are at stake. Give Mr. Trump 90%, or about 100 delegates.

One week later comes Indiana with 57 delegates — the first of the three states where Messrs. Cruz and Kasich have agreed to coordinate. In Indiana, Mr. Kasich is bowing out. While Mr. Trump has maintained a small 6 point lead over Mr. Cruz in the Real Clear Politics average of polls, that has been with the Ohioan in the race and pulling 19%. One would have to believe that one-third to one-half of Mr. Kasich’s supporters will follow their candidate’s signal and switch to the Texan. Mr. Cruz should take the Hoosier State.

The following week, Senator Cruz is heavily favored to win all of Nebraska’s 38 bound delegates. Combined with Indiana, that would offset Mr. Trump’s five-state Northeastern sweep. West Virginia goes to the polls in a contest in which all 34 delegates are elected directly (as in Pennsylvania’s districts) but (unlike in the Quaker State) they are declared and bound. Once again, with Mr. Cruz having been on the ground organizing for months, one has to believe that he has recruited the leading delegate candidates. (Alex Mooney, a sitting U.S. congressman is a Cruz delegate candidate.) Call it a Cruz-Trump split, with each taking 17 delegates.

Next is Oregon, which yields 28 bound delegates and which Mr. Cruz has ceded to Governor Kasich in the second instance of coordination. Oregon is purely proportional. Let’s say the Texan still takes 15%, Mr. Kasich 40% and the New Yorker wins with 45%. Mr. Trump will only get 13 bound delegates.

The final May contest, on May 24, is at Washington. By this time, Mr. Trump will have won only about 30 delegates in the whole month. He will look dead in the water. Mr. Cruz will have won more than three times as many. The functional flip-side of Kasich primacy in Oregon will be a Cruz head start in Washington (44 delegates). Conservatively, let’s say Mr. Kasich just clears the 15% threshold, Mr. Cruz takes 40% and Mr. Trump wins with 45%. Mr. Trump would clear say 25 delegates.

Today, Donald Trump has 845 bound delegates, according to RCP. We’ve accorded him 100 tomorrow and another 55 in May, giving him a round 1,000 going into the final day, supersized June 7, when 310 bound delegates are at stake. He’ll need 237 of those, or three-quarters of them, except that Mr. Cruz is heavily favored in South Dakota and Montana, winner-takes-all states with 59 delegates. So Mr. Trump’s real challenge on June 7 is to take an impossible 237 of the 251 delegates at California, New Jersey, and New Mexico, the third state where Messrs. Cruz and Kasich are coordinating. So Mr. Trump is likely to fall far short of 1,237.

That’s the delegate math. It hinges on Indiana, but the odds are good that the Hoosiers will reverse the psychology and momentum of Mr. Trumps’ northeastern sweep, including New York State a week ago.

Equally important are the implications of the alliance. If Messrs. Cruz and Kasich have agreed to coordinate in this first instance, they will be predisposed to do so the next time and the next. “Way leads on to way,” as the poet Robert Frost observed. Instead of competitors splitting the anti-Trump vote; they’ll be allies optimizing it.

Having coordinated, both candidates will have to align their messaging. After all, the supporters of each will ask for an explanation. Mr. Kasich will have to point out Cruz’s positive attributes and vice versa. There will be cross endorsements. Mr. Kasich’s heretofore inexplicably quixotic quest will acquire meaning and purpose, which will attract support and money — support and money, conditioned upon continued coordination. . The Never-Trump crowd — and money — will reinforce the alliance, giving GOP stalwarts a route to unity after an exceptionally bitter campaign.

Come the convention, all these forces will have deepened the partnership. It gets less difficult to see a Cruz-Kasich ticket coming out of Cleveland. The ideological balance would be there. The outsider-insider partnership. The geographical balance. The swing state of Ohio. A nominee who came in a close second to Mr. Trump in the primaries and caucuses, i.e. a candidate fair and acceptable to most of the angry and alienated base of voters who participated in those contests. What’s not to like for the GOP?

RTJahncke@Gmail.com. @RedJahncke