What's that Republican territory in Brooklyn east of Prospect Park?

[Tintrlvr]

As others have mentioned, that part of Crown Heights is the center of the Lubavitchers, who are one of the larger and more active Hasidic Jewish groups. (They're definitely the group that proselytizes to non-Hasidic Jews the most). It's an odd enclave surrounded by mostly low-income black communities, although the western edge of their community is also on the edge of gentrifying parts of Crown Heights.