CHATTANOOGA, Tenn. (AP) — Employees at a Volkswagen factory in Chattanooga, Tennessee, have voted overwhelmingly in favor of joining the United Auto Workers union, boosting the UAW’s nationwide effort to organize nonunion factories. The union wound up getting 73% of the ballots cast in an election run by the National Labor Relations Board that ended Friday. Twice in recent years, workers at the Chattanooga plant have rejected union membership. But this time, they voted convincingly for the UAW, which is operating under new leadership directly elected by members for the first time and basking in a successful confrontation with Detroit’s major automakers.