Union organizers in states like Tennessee are hoping to change that. Since 2010, the number of union members in Tennessee has grown from 115,000 to 155,000. Still, only 5.7 percent of Tennessee workers are members of a union.How To Patrick Green, even one new member is a big deal. Green is a president of Local 1235, which is part of the Amalgamated Transit Union in Nashville, Tennessee. In the three years that he has been leading the union, the local’s membership rate went up by 36 percent, despite being in a right-to-work state.