The regional director of the National Labor Relations Board's Tampa, Florida office filed a complaint on Tuesday claiming unlawful threats, retaliation and surveillance by Starbucks managers were so severe that holding a new election at the store would be futile.

Starbucks did not immediately respond to a request for comment on Thursday.

Workers at the Estero, Florida store voted 21-11 in May against forming a union amid a nationwide organizing campaign that has involved hundreds of Starbucks locations.

The campaign, Starbucks Workers United, has won elections at more than 260 U.S. stores and has lost about 70 elections since late 2021. The union is seeking increased pay and benefits, improved health and safety conditions and protections against unfair firings and discipline.

The new complaint claims that in the weeks leading up to the election at the Estero store, managers threatened to withhold raises, supervised workers more closely than usual and held mandatory anti-union meetings.

The regional director is asking the board to issue a "bargaining order" forcing Starbucks to recognize and bargain with the union at the Estero store.

The NLRB only issues bargaining orders in cases where it finds severe misconduct that cannot be addressed by traditional remedies, such as requiring employers to post notices of violations.

Starbucks is facing similar claims in a pending case involving a Buffalo, New York store where workers voted against unionizing in 2021. The company has generally denied wrongdoing in response to the union's dozens of claims of misconduct.

The complaint will be heard by an administrative law judge, whose decision can be appealed to the five-member board and ultimately to a federal appeals court.

(Reporting by Daniel Wiessner in Albany, New York, Editing by Alexia Garamfalvi and Bernadette Baum)

By Daniel Wiessner