Donald Trump’s New York Supremacy Doesn’t Guarantee His Nomination

He still needs a lot of delegates.

Donald Trump's romp through New York on Tuesday begins what will be a rampage through the next few weeks, as the race shifts toward the Trump-friendly territory of the Mid-Atlantic and Northeast.

The coming run, though, won't be enough to guarantee Trump the Republican presidential nomination. For him to lock down victory before the GOP convention in July, the final states out West, including California, will be key.

Once the dust settles in New York, 674 of the Republican Party's 2,472 delegates will remain for the candidates to claim. Simple math leaves it increasingly clear that Sen. Ted Cruz (R-Texas) and Ohio Gov. John Kasich have no chance of winning the nomination outright.

The likelihood of a contested convention hinges on how likely Trump is to get almost 60 percent of the remaining delegates. Assuming he wins about 85 delegates, as expected, in New York, he'll be about 51 delegates shy of staying on track to reach a majority in June, according to FiveThirtyEight’s targets. That’s not insurmountable. But racking up 396 of the remaining 674 delegates won’t be easy.

Trump has yet to get 60 percent of the vote in any state -- although it looks like he could top that mark in New York. Like New York, however, many of the remaining states allocate delegates by congressional district, which means Trump could win a state, but still lose a substantial number of delegates by failing to win individual districts. Or he could squeak by in a state, yet walk away with a bus full of delegates by winning each district.

Next week’s primaries include a swath of the East Coast -- Connecticut, Delaware, Maryland, Pennsylvania and Rhode Island -- that has so far proved favorable to Trump. Polls in Pennsylvania and Maryland show Trump comfortably ahead, though falling short of a majority. There's less data in the remaining states, but their demographics suggest similar results.

The real wild card is that most of Pennsylvania’s delegates are unbound and don’t have to declare a preference. That means Trump could win the state -- and he’s ahead in the polls by an average of 18 points -- but only come away with 17 pledged delegates if the 54 unbound delegates are swayed to another candidate.

Those East Coast states are followed by several primaries in the Cruz-friendly Mountain West -- Oregon, Washington, Montana, and New Mexico. Nebraska, West Virginia and South Dakota account for an additional chunk of delegates, but there’s no polling in those states indicating who might win. West Virginia is likely to be Trump country, while South Dakota and Nebraska lean for Cruz.

The most significant states remaining after those contests to help Trump are Indiana, California and New Jersey.

California and New Jersey are prime territory for Trump to pick up a lot of delegates. He leads by an average of 15 points in California and by nearly 30 points in New Jersey. Indiana is more likely to be a tossup, heightening the importance of the race there.

Those Trump leads, however, won't necessarily translate into equally big delegate wins. In California, as in New York, many delegates are allocated at the congressional district level, so Trump will need to turn statewide wins into district-level romps to convert as many delegates as possible.

If Trump gets close to the 1,237-delegate mark, but falls short of it, the contests for unbound and statewide delegates become even more important. That’s not an area where Trump has excelled.

Cruz and Kasich, in some ways, have an easier job ahead of them. Since neither can win the nomination outright, they are scanning the map to figure out how and where they can deny Trump delegates, whether it's by campaigning hard in single districts, as Kasich did in New York, or organizing at the party level to lure away delegates Trump thought he had in his hands, as Cruz has done.