If you think Donald Trump is on an unstoppable path to the Republican nomination, you haven’t done the delegate math. He can still be stopped – but at this point probably only by [crscore]Ted Cruz[/crscore].

John Kasich and [crscore]Marco Rubio[/crscore] should be thinking very hard about what their end games are after Tuesday night’s election results. Rubio won zero delegates, placing dead last in two states and second to last in two others. Kasich, who has yet to win a single state, couldn’t even win in Michigan and seems to be basing his entire campaign on winning his home state of Ohio.

It is Ted Cruz who has emerged as the most viable non-Trump candidate in the field. If Kasich and Rubio believe that the finger-length impaired Republican front-runner would destroy the conservative movement and tear the Republican Party apart, they must unite behind Cruz to stop him.

And stop him Cruz can. While it is unlikely Cruz will be able to amass the 1,237 delegates needed to win the Republican nomination outright on the first ballot, he certainly has a path to go into the Republican convention with a delegate lead, even a significant one. But to have a shot at that he needs a one-on-one race with Trump, who regularly brags about attending the Wharton School but allegedly only got in because his brother had a friend on the admissions committee.

While Trump, who does not appear on Bloomberg’s list of the 200 wealthiest people in the world, is doing well in a four-person contest, there is reason to believe he would have trouble garnering more than 50 percent of the vote in many –perhaps any — states in a two-man race. A NBC/Wall Street Journal poll released Tuesday showed that in a one-on-one race, Cruz leads Trump (who some say is six-foot two at best) by 17 percentage points nationally.

Now, the Republican primary is not run nationally. It is run state-by-state. But such a large national head-t0-head lead suggests Cruz would be competitive in every state against Trump, who reportedly once asked comedians not to make fun of him for being worth less than he says he is, in a one-on-one race.

But will Rubio and Kasich get out of the race to give the non-Trump movement the best chance of defeating the billionaire golf cheater? Both have said they plan to fight on until the March 15 primaries in their home states of Florida and Ohio. But even if both win their home states, what exactly are their respective paths to the nomination? Hoping that the Republican convention awards them the nomination on the second or third ballot in a contested convention, even if they are far behind Trump, who once tried to kiss a dress-wearing Rudy Giuliani, and Cruz in the delegate race? This is not a serious strategy and even if it somehow panned out, it would probably doom the Republicans’ prospects in November.

Ideally, Kasich and Rubio would come to an agreement with Cruz to do whatever he needs to give him the best chance to defeat Trump. Maybe that’s staying in the race through March 15 to try to deny Trump delegates in the winner-take-all states of Florida and Ohio. Maybe that’s dropping out now. Whatever Cruz requests, they should do.

But without a deal where Rubio and Kasich commit to leaving on March 15 at the latest, regardless of what happens in Ohio and Florida, Cruz has to do his best to ensure Trump, who occasionally takes pretty weird pictures with his daughter, wins in Ohio and Florida (assuming he can’t win those states himself) to get those candidates to drop out. Because even if Trump, who seems to think going to a military prep school is actually like being in the military, wins Ohio and Florida next week, Cruz can overcome his delegate lead in a one-on-one race.

Of course, the operative word is can. There is no guarantee that Cruz would stop Trump, who regularly asks people to touch his hair to prove it is real, one-on-one. Perhaps we will learn that Trump, who reportedly used to keep a book of Hitler’s speeches next to his bed, is able to clear 50 percent support in many states. Perhaps when Trump, who is so secure with himself that he once sued a reporter for $5 billion dollars for suggesting he might actually only be a millionaire, focuses his rhetorical skills on Cruz, he will destroy Cruz’s candidacy, like he destroyed the candidacy of Jeb Bush.

Anything is possible. But if you are apart of the #NeverTrump movement, at this point it’s Cruz or lose.

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