Workers at a downtown Pleasanton Starbucks store have formally launched an attempt to unionize, joining a growing nationwide trend of employees grappling for better pay and job security amid a challenging economy.

The employees at the store want to join the Starbucks Workers United union, like employees at three other Bay Area stores and others nationwide, organizers said.

Employees — or partners as they are also called at the store, located at Main Street and Rose Avenue — filed a petition March 3 with the National Labor Relations Board to unionize.

Workers said in a letter to Starbucks Chief Executive Officer Howard Schultz that they received an unexplained cut in hours and are finding it challenging to pay their bills. The employees also feel their needs are being neglected regularly.

“We are unionizing because we have tried everything else,” said Elise Lester, a partner and organizer at the Pleasanton store. “It is time we have a say in decisions that directly affect us and our livelihoods.”

Starbucks’ corporate office did not immediately respond to a request for comment on the action by the Pleasanton store’s workers.