Donald Trump has a good chance to effectively wrap things up on March 15. Polls show him with a 20-point lead in Florida (where early voting opened as Marco Rubio was tanking), putting him on track to take all of its 99 delegates in the winner-take-all primary. If Rubio fails to win Florida, it’s difficult to see him staying in the race. Here’s how our model sees that race playing out:
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Change four variables, though, and the race takes on a different flavor:
- Rubio drops out after Florida. His supporters go 75% to Kasich, 20% to Cruz, and 5% to Trump (yes, that’s a total guess).
- Kasich wins Ohio. This isn’t a huge stretch; he leads Trump in current polling averages, and the 6-7% Rubio numbers may heed his strategic-voting advice.
- Trump’s poll numbers are his ceiling. Until our last update, our model split the “undecided” votes (i.e. the difference between 100 and the sum of the candidates’ support) proportionally. We’ve added a number of different scenarios. The one that tracks most closely to reality is that Trump’s polls are his ceiling; the biggest difference in his favor, according to the excellent fivethirtyeight.com poll average, was the 3.3% miss in Massachusetts. On average, he comes in below his polls 1-2%.
- Cruz wins Illinois. He trails Trump by 6 points in the late fivethirtyeight.com average, but when we apply the “Trump ceiling” rule, he comes within a single point.
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Based on that, Trump misses. the target by about 20 votes. Still not an ideal outcome for the #NeverTrump camp, but it doesn’t require too many logical leaps.
Stretching a bit further into supposition, Rubio’s dropout could broaden the gap:
- Kasich or Cruz win Pennsylvania. Rubio dropping out would put the three remaining candidates within a point or two of each other (possibly favoring Kasich, as Rubio still polls strongly here). Kasich may end up off the ballot, though.
- Kasich or Cruz win Maryland. There, they really would all get a third under our polling split.
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This setup would already have Cruz winning Wisconsin and Kasich winning California, based on Rubio’s support pushing them over the edge. That’s about as close to a NeverTrump dream scenario that the numbers currently bear out. It would have the weird effect of an all-out fight in California (!), but perhaps March 15 will shed a bit more light on Rubio’s future, and on Trump’s ceiling.