The long-time head of Mexico's national teachers union has been elected to another six years as its president.

Elba Esther Gordillo is among the most politically powerful women in Mexico. She has headed the union since 1989.

The union said the vast majority of more than 3,000 delegates voting at a convention Saturday cast their ballots for Gordillo.

Gordillo was an influential figure in the presidential election earlier this year, which was won by Enrique Pena Nieto of the Institutional Revolutionary Party. The party known as the PRI controlled Mexico's presidency for seven decades until it lost in 2000 to the conservative National Action Party.

During its years in power, the PRI counted on labor groups like the teachers union for political support.