You can hope it doesn't come back, but if there is crabgrass seed in your soil (odds are good there is), it will come back. Crabgrass is a warm season annual. It germinates when soil temps are above 60 degrees for three to seven consecutive days, flourishes in late spring till frost in fall. It can lay down a lot of seeds in your lawn, that will lie dormant till next year. It is pretty late in spring to seed a lawn now, you would be well advised to wait till late summer, around Sept. 1-15. If you seed now, the only way to prevent crabgrass germination (if it hasn't started yet, not sure of your soil temps in NJ) is by using Tupersan, and using it every 4-6 weeks. It won't affect turf seed, it will however prevent crabgrass from germinating. It isn't cheap however. If you wait till late summer, you can put down a stronger preemergent called Dimension, which will prevent crabgrass germination for about 3 months. For cool season grasses the best schedule is preemergents in late winter/early spring, spot spray weeds in spring and summer, seed in late summer/early fall. If you don't need to seed then another round of preemergents in late summer is recommended to prevent winter annuals like poa annua from germinating.

The best thing you can do for this season is turn the clock back to last fall and do what you just did this spring. Crabgrass seed germinates now. When you do your seeding in the fall you don't get so much crabgrass. Then you have all fall for the lawn grass to mature and by spring you don't have to do anything but mow and water.