MONTICELLO, N.Y. — Sherelle Baker was spending more money on gas driving to work from her home here than she made at the job as a waitress-bartender. Then her hours got cut.

But in mid-December, Ms. Baker walked out of a job fair at the local Ramada Inn with a new position at the soon-to-open Resorts World Catskills, the $1.2 billion casino resort that proponents say will revive Sullivan County, a once-booming area known as the borscht belt for its hotels, bungalow colonies and performers, appealing to Jewish vacationers.

“It seems like there’s this gray cloud over Monticello,” said Ms. Baker, 24, who was gleeful about her new job at the front desk of the casino’s hotel, which came with a $7-an-hour pay increase and medical benefits. “Hopefully, this casino will bring more life, more traffic and more business to town.”

The 18-story casino and hotel rises above the tree line on the former grounds of the Concord, the grande dame of the borscht belt, outside Monticello. The building — with 332 suites, bars, restaurants and a 2,000-seat event center — is flanked by the reconfigured Monster golf course; a year-round indoor water park and lodge is under construction nearby that will offer more restaurants, as well as hiking and zip lines.