Deutsch’s problem is a) a lot of frum people are registered Republicans, and thus cannot vote for him in the Democrat primary and b) even if every frum registered voter was a registered Democrat, the Congressional district is majority black, with the frum community representing probably less than 20% of the district population.
In fact, unfortunately for the frum community, the frum neighborhoods are cut down the middle and split between Congressman Jerold Nadler’s district and Congresswoman Yvette Clarke’s district, hence splitting the community in two different Congressional districts.