Correct. It was a closed primary. There are way more registered Dems in NY than Repubs.
How many independents will vote for Trump in the general election? That’s the key question. He may get enough of them to defeat Hillary.
Enrollment statistics don’t mean much in NY. A lot of NY Democrats are DINOs who vote like Independents in the general.
I might add that a lot of NY voters enroll in a party only because they know that’s how you get to vote in primaries. And most of the interesting primary races in NY are between Democrats. So this inflates Democrat enrollment. Getting those votes in the fall is another matter.
Another reason to enroll Democrat is to be able to get in on patronage. The Democrat bosses still want to know: Are you a Democrat? And do you contribute? Or will you?