MEXICO CITY -- Workers at a General Motors plant in Mexico have voted to end a collective bargaining contract negotiated by an old guard union accused of intimidation tactics in earlier votes. It was an early display of the effectiveness of labor mechanisms negotiated under the U.S.-Mexico-Canada Trade Agreement.

Nearly 6,000 workers at the GM plant in Silao voted over two days, according to a statement from Mexico’s Labor Ministry on Thursday. In the final tally, the “nos” were 3,214 to 2,623 votes in favor.

The vote means the contract is terminated, but the workers maintain the same benefits and labor conditions. The vote was a rejection of the union, part of the Confederation of Mexican Workers. A new group has been working to organize the plant’s workers.

The vote spanned Tuesday and Wednesday and was held inside the plant with observers from the Labor Ministry, National Electoral Institute and the United Nations’ International Labor Organization.

The conditions for the vote “demonstrate the government’s commitment to union democracy and respecting the will of the workers,” the Labor Ministry said in the statement.