Updated from 1:12 p.m. ESTThe International Association of Machinists is set to unveil plans on Tuesday to organize about 15,000 fleet-service workers and customer-service agents at Continental Airlines ( CAL). The move follows the completion of negotiations between the airline and its flight attendants, who are also represented by the IAM. "We have received expressions of interest from a large number of Continental fleet-service workers and customer-service agents," IAM spokesman Joe Tiberi said Monday. In January, flight attendants approved an agreement with the Houston-based carrier that called for $72 million in concessions, but the arrangement also includes a no-furlough clause, increases in some benefits and the retention of a defined-benefit pension plan. A Continental spokesman declined to comment. The IAM will begin to collect signed cards requesting an election from Continental employees. Although the National Mediation Board can call an election with cards from 35% of a proposed bargaining unit, Tiberi said the union intends to submit cards from more than 50%. "You need more than 50% to have a successful campaign," he said. Last July, the Transport Workers Union failed in a bid to organize about 7,000 Continental fleet-service workers. TWU spokesman Jim Gannon said that a new bid is underway and that about one-third of the group has signed cards seeking an election, but labor law prevents filing for a new election until a year after the previous vote. The IAM already represents fleet-service and customer-service agents at both Northwest Airlines ( NWACQ)B and UAL ( UAUA) unit United Airlines, as well as fleet workers and mechanics at US Airways Group's ( LCC) US Airways unit. Tiberi noted that the IAM has also received expressions of interest from workers at JetBlue Airways ( JBLU), but for the moment, he said, the union will focus its organizing efforts on Continental.