(The Hill) — Employees at more than 50 Starbucks locations have petitioned to unionize shortly after workers at a Buffalo, New York, store first voted to do so last month. 

Workers United, an affiliate of the Service Employees International Union that is organizing the Starbucks push, said Monday that an additional 15 locations filed for union elections with the National Labor Relations Board. 

With the most recent announcement, 54 Starbucks locations in 19 states have petitioned to unionize, indicating that the organizing effort is spreading rapidly. 

“Our movement is only growing,” the labor union tweeted on Monday. “Partners around the country are standing up for what’s right and we couldn’t be more inspired!”

Starbucks has urged its employees to push back on the unionization effort. The coffee chain said last month that it did not want unions to come between the company and its workers, but pledged to “respect the legal process” and “bargain in good faith” with the Buffalo store that voted 19-8 to unionize. 

“Our hope is that union representatives also come to the table with mutual good faith, respect and positive intent,” Rossann Williams, the company’s president of retail for North America, wrote in a letter to employees. 

Earlier this month, a separate Buffalo location became the second Starbucks store to unionize following a 15-9 vote. Another store is awaiting vote results and a fourth store in Arizona will count votes on Feb. 16, according to Workers United. 

The Hill has reached out to Starbucks for comment.