RALEIGH (AP) -- Smithfield Foods says more than half of its 5,000 employees have signed letters asking a union trying to organize the plant to allow a vote.

The United Food and Commercial Workers have been trying for more than a decade to organize the world's largest hog slaughterhouse, located in Tar Heel.

Smithfield officials say they offered employees letters addressed to the union's president asking for a vote. Nearly three-thousand of the employees signed the letter.

Union activists have opposed the company's strategy and want card-check organizing, which would force the company to recognize a union if the group can get more than half of employees to sign a card.