Ted Cruz Might Still Be Able To Stop Donald Trump All he needs is for Rubio to drop out three weeks ago.

The good news for the Republican “establishment” is that there’s a man who might be able to stop Donald Trump. The bad news is that it’s Ted Cruz, someone they may dislike almost as much.

Cruz, who won Idaho on Tuesday while finishing second to Trump in Michigan, Mississippi and Hawaii, is within striking distance of Trump. So far, 29 percent of Republican primary voters have voted for Cruz as compared with 35 percent for Trump. Meanwhile, Cruz trails Trump by 100 delegates: not a trivial gap, although only one more than the 99 at stake in winner-take-all Florida next Tuesday.

The problem for Cruz is that Florida and the rest of the calendar probably aren’t as favorable to him as the states that have voted so far. (Florida looks like a Trump state as Marco Rubio loses ground.) But Cruz does have a few things going for him. He’s tended to outperform his polling almost everywhere. He’s won states in all four major regions of the country. And he potentially stands to gain if Rubio and perhaps John Kasich drop out.

The exit polls in Michigan and Mississippi asked voters who they’d pick in a two-way race between Trump and Cruz, also giving them the option to say they’d sit out the race. Among Rubio voters, on average between the two states, about 75 percent said they’d still vote in a Trump-Cruz race, and of those, 80 percent would prefer Cruz to Trump. Kasich voters were somewhat more equivocal; 55 percent said they’d still vote, and of those, two-thirds would go to Cruz over Trump. Although this is the first time the exit polls have asked about one-on-one matchups, the results are consistent with national polls showing Trump losing ground as the field winnows, as well as exit polls in previous states showing Trump being unpopular with Republicans who aren’t already supporting him.

What would the rest of the map (and more importantly, the delegate tally) look like in a potential two-way race between Trump and Cruz? I’m not ready to predict that. Beyond Florida and Ohio, which vote on Tuesday, there isn’t much polling in the other states. Nor has the Republican race been all that predictable along demographic lines, with Trump having performed well in states as diverse as Massachusetts, Alabama and Hawaii.

What I will do, however, is “retrodict” how the race might have gone had it been a two-man contest between Cruz and Trump all along. Could Cruz have beaten Trump in South Carolina, for instance? To do this, I’ll redistribute support from Rubio, Kasich and other candidates to Cruz and Trump based on the exit poll answers I described above. To repeat, these assume that most of their support would have gone to Cruz but not all of it, and also that a fair number of voters (especially Kasich voters) would sit out the race without their candidate on the ballot.

Here’s how things might have looked:

ESTIMATED SHARE OF VOTE DELEGATES UNDER UNIFORM GOP RULES DATE STATE TRUMP CRUZ TRUMP CRUZ Feb. 1 Iowa 40.7 59.3 5 23 Feb. 9 New Hampshire 57.3 41.0 18 4 Feb. 20 South Carolina 47.6 52.3 10 37 Feb. 23 Nevada 56.7 42.9 22 6 March 1 Alabama 55.4 42.4 37 10 Alaska 43.4 56.6 6 21 Arkansas 43.1 54.5 8 30 Georgia 50.7 48.0 55 17 Massachusetts 64.9 32.5 34 6 Minnesota 34.7 65.2 6 30 Oklahoma 38.5 60.0 8 33 Tennessee 50.3 47.4 42 13 Texas 34.1 62.7 24 123 Vermont 53.3 43.0 12 3 Virginia 49.9 48.9 32 15 March 5 Kansas 30.5 68.4 6 32 Kentucky 45.9 52.4 10 34 Louisiana 47.0 49.8 14 30 Maine 39.0 59.7 4 18 March 6 Puerto Rico 29.8 64.2 3 19 March 8 Hawaii 50.4 48.4 14 4 Idaho 34.4 62.4 5 25 Michigan 49.2 45.7 39 17 Mississippi 52.5 45.0 30 8 Total 444 558 Share of delegates 42% 53% What if Trump and Cruz had run one-on-one?

These figures estimate that Cruz would have won South Carolina, Arkansas, Kentucky and Louisiana in addition to the states where he already beat Trump. He also would have won Minnesota and Puerto Rico, which originally went to Rubio. Several other states, such as Michigan, Georgia and Virginia, would have been close between Trump and Cruz. Trump would be fairly dominant in the Northeast, however, and would still have won Nevada easily.

Overall, however, it’s likely that Cruz would have a delegate lead on Trump. I haven’t gone through each state’s delegate rules in detail, which would require estimating the vote by congressional district. Instead, I’ve applied something I call “uniform Republican rules,” which I introduced in a previous article. These are simplified delegate rules that give one-third of the delegates to the winner in each state, with an additional bonus for finishing with more than 50 percent of the vote, and distribute most of the rest proportionately. (The uniform rules also assign a small number of unpledged delegates in each state; these are not shown in the table.) Basically, they represent a compromise between winner-take-all and proportional methods that roughly reflects the rules in the average Republican primary and that approximates actual delegate allocations reasonably well.

Under these rules, Cruz would have 558 delegates to 444 for Trump. So instead of trailing Trump by 100 delegates, he’d lead him by roughly that amount instead.

This might sound too optimistic for Cruz, and certainly there are things a method like this can’t account for. (If Cruz had won South Carolina rather than Trump, for example, it would have changed media coverage of the race.) But keep in mind that Cruz is doing most of the work himself — he hasn’t trailed Trump by all that much in the states that have voted. So giving him even some of the Rubio and Kasich voters is enough to put him over the top in several states that he narrowly lost.

Perhaps we shouldn’t be grouping Rubio and Kasich together, however. Whereas Rubio’s numbers have been going downhill in Florida and other places, Kasich is even money or maybe a little better to win Ohio. And if he’s sustained himself this long on the basis of little more than a few second-place finishes in the Northeast, why would he drop out if he wins his home state?

The exit polls haven’t asked many questions about how supporters of the other candidates view Kasich, so we’ll assume that Kasich gets about as many votes from Rubio as Cruz does. (This makes a certain amount of sense: Rubio supporters have more in common with Kasich voters demographically but more in common with Cruz voters ideologically.) Specifically, we’ll assume that support from former Rubio voters goes 42.5 percent to Cruz, 42.5 percent to Kasich and 15 percent to Trump. We’ll also assume that 80 percent of them still vote, slightly up from 75 percent because we’ve given them another option. Kasich also gets to keep all of his own supporters, obviously. Here’s how that would shake out:

ESTIMATED SHARE OF VOTE DELEGATES UNDER UNIFORM GOP RULES DATE STATE TRUMP CRUZ KASICH TRUMP CRUZ KASICH Feb. 1 Iowa 36.3 47.5 16.2 7 19 3 Feb. 9 New Hampshire 46.4 23.7 28.2 15 3 4 Feb. 20 South Carolina 41.9 37.8 20.2 30 11 6 Feb. 23 Nevada 53.1 33.3 13.2 23 5 0 March 1 Alabama 51.4 33.3 13.1 38 9 0 Alaska 40.2 48.4 11.4 8 19 0 Arkansas 39.7 44.0 13.9 12 26 0 Georgia 46.2 36.6 15.9 47 17 8 Massachusetts 54.5 17.3 25.6 32 3 5 Minnesota 30.1 48.6 21.3 7 24 5 Oklahoma 35.3 48.9 14.3 11 30 0 Tennessee 46.2 37.0 14.5 39 16 0 Texas 31.4 54.0 11.5 25 122 0 Vermont 37.9 18.7 39.7 4 2 9 Virginia 43.4 32.5 23.0 30 10 7 March 5 Kansas 26.2 55.8 17.0 5 30 3 Kentucky 39.2 38.5 20.7 27 11 6 Louisiana 43.8 42.6 10.4 30 14 0 Maine 34.1 49.4 15.2 5 15 2 March 6 Puerto Rico 25.5 38.6 30.0 4 14 4 March 8 Hawaii 45.2 38.2 15.5 11 5 2 Idaho 31.0 52.5 13.2 5 25 0 Michigan 38.4 28.6 27.9 35 11 11 Mississippi 48.4 38.4 10.6 27 11 0 Total 477 452 75 Share of delegates 45% 43% 7% Kasich could cost Trump votes but give him states

Kasich wins Vermont under this math, but that’s the only state he gets. Meanwhile, the votes Kasich takes back from Cruz allow Trump to narrowly win South Carolina, Kentucky and Louisiana, when he would have lost them in a two-way race.

Overall, under uniform delegate rules, Trump wins slightly more delegates with Kasich running than without! Even though he wins fewer votes, the winner-take-all bonuses really help him. Cruz falls back behind Trump, meanwhile, while Kasich still isn’t doing that well, with only 75 delegates to date.

So if Republicans want to stop Trump from being their nominee, they should encourage Kasich (along with Rubio) to drop his bid? That’s one reasonable interpretation of this data, yes. Trump’s great weakness is that he loses ground as other candidates drop out. The most parsimonious strategy is just to get it to a one-on-one race.

However, I think the details make the case a bit more equivocal than that. Kasich could make a few good arguments for staying in the race:

O-H-I-O.

Southern states, Kasich’s weakest region, are overrepresented so far.

Cruz is weak in the Northeast, and even if Kasich can’t win those states, he might be able to prevent Trump from hitting winner-take-all thresholds in states like New York, where a candidate wins all statewide or congressional district delegates if he gets more than 50 percent of the vote.

Rubio voters probably wouldn’t just split their votes 50-50; instead, they could behave tactically, going to Kasich in Connecticut (for example) but Cruz in Arizona.

Overall, I think it’s a close call between Cruz and Kasich having a better shot of stopping Trump as a tandem or Cruz being better off on his own. Kasich doesn’t appear likely to drop out before Ohio, in any event, so what happens there will probably go a long way toward determining his plans.

Rubio’s chances are hanging by a thread, however. He’ll presumably drop out if he loses Florida, but there’s an argument that his chances are slim enough in Florida that anti-Trump Republicans would be better off if Rubio dropped out immediately, which would give Cruz and Kasich better chances to win delegates in Ohio, Illinois, Missouri and North Carolina, all of which also vote Tuesday.

Either way, there’s likely to be some sort of endgame after March 15. Even if Trump wins both Ohio and Florida, Cruz might run relatively well against him in a one-on-one race from that point forward. Would it be too little and too late, especially with a lot of states in Trump’s northeastern base still left to vote? Possibly, but Republican “party elites” would finally have to make the very choice they were most hoping to avoid.

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