NEWARK—As Cory Booker's term as mayor potentially draws to a close, he can finally claim victory in a very personal battle: His city is getting a Whole Foods .

The specialty grocer is slated to announce Thursday that it has signed a lease to open a 29,000-square-foot store in the heart of the city's downtown.

For Mr. Booker, a vegetarian and foodie who began courting the chain soon after his inauguration in 2006, the store helps fulfill a promise to bring more fresh food to the city. He called and texted Whole Foods executives for years while pursuing the grocer, and mentioned his love of the chain on the city's WBGO radio station.

"It almost became for me like the quest for the Holy Grail," Mr. Booker said in an interview. "This would be the sign that Newark had fully turned a corner."

But it is more than a personal victory. The store's opening is also a sign that Newark—a city of 277,700 long seen by some higher-end retailers as too gritty—is gaining some cachet.