Donald Trump won big in his home state of New York, collecting at least 84 of the 95 delegates at stake.
John Kasich won at least two delegates and Ted Cruz was in danger of being shut out.
Nine delegates were still left to be allocated.
Trump won big by getting more than 50 percent of the vote - statewide and in a majority of individual congressional districts.
New York awards most of its delegates according to vote totals in individual congressional districts.
The win could help put Trump on a path to win the nomination by the end of the primaries on June 7 - if he can keep winning.