It was not a clarifying Super Tuesday. It was almost a blowout Super Tuesday. For each of the four delegate leaders in the Republican race, Tuesday night taught them something worrying about the nomination fight.

Ted Cruz’s Southern strategy failed. Almost nobody has uttered the word “firewall” this year without getting burnt. Ted Cruz was no exception. “I view the SEC primary as a firewall,” Cruz told donors at a Koch summit in the summer, as he began methodically making campaign stops and racking up endorsements in Southern states. The “SEC primary” consisted of the deep South states — Virginia, Georgia, Tennessee, Arkansas and Alabama — that moved their contests to March 1. “My 19-month-old daughter couldn’t color a map that’s better for us on March 1,” Cruz campaign manager Jeff Roe told Politico in the autumn.

She will need a new coloring book. Cruz got blown out in the deep South. He won no counties whatsoever in Virginia, Georgia, Tennessee and Alabama. In Tennessee, seen early on as an SEC bellwether, Cruz lost veterans by 9 points, evangelicals by 14 points and voters without college degrees by 21 points. Trump dominated what was supposed to be Cruz’s base — what, frankly, was expected to be his base in the long-ago days when pundits assumed Trump would collapse.

The media’s focus on whether Cruz would “win his home state” — a discussion Cruz was happy to have — briefly distracted from the Dixie massacre. Cruz’s strength in Minnesota and wins in Oklahoma and Alaska pointed at a strategy for picking up delegates in this month’s caucuses and Midwestern primaries. And he gained plenty of delegates across the South. The fact remains: He said he would blow it out in the SEC primary, and he did not.

Endorsements can’t pull Rubio over the finish line. In four states now — Arkansas, Oklahoma, Tennessee and South Carolina — Rubio has attempted to surge over the top with the support of popular Republican governors. He has failed every time. In the first three states, he could not beat Cruz for second place. The greatest determinant of Rubio’s success is not whether he’s won local endorsements, but whether a state has a dominant suburban vote. That was his salvation in Minnesota, where the four congressional districts around the Twin Cities cast most of the vote, and Rubio won. (Rubio’s state chairman in Minnesota, Jeff Johnson, had been the unsuccessful 2014 nominee for governor.)

If this matters, it’s because Rubio, more than anyone in the field, is pining for his party’s statesmen (and donors) to get behind him already. Rubio allies in the social conservative movement had been saying, mostly to the sharp-eyed National Review reporter Tim Alberta, that if Cruz stumbled badly on Super Tuesday, conservative leaders were ready to shift to Rubio. Only, ironically, in the Beltway suburbs where many Republican strategists live did Rubio do markedly better than Cruz. It remains true that Rubio polls better than Cruz in November ballot tests, and that the Republican establishment likes Rubio much better than Cruz, but it’s unclear what it can do about that.

John Kasich doesn’t have a reason to quit yet. Sure, he proved the fool’s good value of endorsements even better than Rubio. (Kasich won the endorsement of Alabama Gov. Robert Bentley and came in a poor fifth place.) But the Republicans arguing that Ohio’s governor spoiled things for Rubio are focused on just one state: Virginia. There, Kasich absolutely worked to keep Rubio from a win, making a Tuesday fly-in to Arlington. In the counties and cities closest to Washington, yes, Kasich won enough votes that — had they all gone to Rubio — would have dramatically changed the tone of the race by denying Trump the state.

But the Kasich votes are not LEGO blocks to be painted Rubio red. His voters remain skeptical of Rubio, and even if they weren’t, in most states there aren’t enough of them to push Rubio over the top. In the other closest Super Tuesday states of Oklahoma and Arkansas, had every Kasich voter swung to Rubio, Rubio still would have lost. And the chances of Kasich bailing on the race before March 15, when both Ohio and Florida vote, is nonexistent.

Donald Trump can’t close the deal. It sounds funny, but he can’t. In the deep South, Trump was helped massively by early voting, because he consistently lost late-deciders. In Tennessee, just 21 percent of people who decided to vote “in the last few days” backed Trump, putting him third behind Cruz and Rubio. In Virginia, which Trump nearly lost, just 18 percent of late-deciders chose him. (That was in a heretofore unique situation where many liberal voters, seeing no close contest on their ballot, voted to stop Trump.) In just one of the states he won, Massachusetts, did Trump win late-deciders, and that was in a place that everyone else except Kasich had abandoned. (Trump won late-deciders 32-26 over Kasich.)

In every case, the late movement away from Trump cost him delegates. He missed out on a big delegate lead by falling just below 50 percent in Massachusetts. Rubio’s late surge in Virginia muddled the delegate picture. Wednesday, Republican strategists are telling themselves that voters demonstrated how Trump could be brought down.

“This isn’t a typical nomination fight, where the front-runner gains momentum from week to week,” said Tim Miller, the former Jeb Bush communications director who Tuesday night joined the stop-Trump group Our Principles PAC. “He’s losing momentum.”

(c) 2016, The Washington Post · David Weigel