New management at Chipotle Mexican Grill will grow sales at the burrito chain through an improved menu, digital and delivery offerings and other marketing successes, according to RBC Capital Markets, which upgraded shares to outperform.

But investors may need to wait until next year before they see the actual results in the chain, which has been trying to emerge from a series of health scares.

"After a 19 percent retreat from recent highs, we believe Chipotle shares offer a compelling risk/reward heading into 2019 and 2020," David Palmer wrote in a note. "We believe there is a favorable stock set-up into 2019 given menu innovation, digital initiatives, and a focus on improving restaurant margins."

Third-quarter results are expected to be just "lackluster," the analyst said in a note to clients Monday, but sales should improve next year under CEO Brian Niccol's push for food innovation and customers remain loyal despite prior food safety concerns.

In addition to the stock upgrade, the analyst raised his 12-month price target on Chipotle shares to $510 from $450, representing 19 percent upside from Friday's close. Shares of Chipotle rose 1.7 percent in premarket trading following the RBC upgrade.

Much of Palmer's newfound conviction on Chipotle shares came from a new RBC survey in which more than 1,000 respondents answered questions about their recent visits, or lack thereof, to a CMG restaurant.

Source: RBC Capital Markets

The analyst said the survey resulted in four key findings: Chipotle remains in the top three favorite chains of all quick-service restaurants, there's a sizable opportunity to increase awareness of its digital capabilities, existing and lapsed customers are willing to try new offerings and food safety is only a small reason why customers do not eat at Chipotle.

"What has sometimes been lost upon investors over the last three years has been that Chipotle continues to have one of the most loyal followings across all consumer brands," Palmer said. "Chipotle ranks behind only Chick-Fil-A and Panera Bread in restaurant popularity among all respondents of the survey."

Any progress is likely welcome news to investors including Pershing Square activist Bill Ackman, who has leveraged his stake in the company to promote ideas like drive-thrus and breakfast offerings following a pullback in shares in the wake of the food safety incidents.

Ackman applauded the appointment of Niccol as chief executive officer earlier this year. Niccol joined Chipotle following a successful track record at Taco Bell.

"We're not just betting on a recovery from the food safety issue," Ackman told CNBC in November. "This is one of the least optimized of the quick-service restaurants."

Shares of the casual Mexican restaurant are up 48 percent since January.