For the past seven years, instructors have crossed the country offering driver-education seminars and recruiting conscientious drivers to compete in the Brandhouse Number-One Taxi Driver competition, sponsored by the South African distributor for liquor brands including Jose Cuervo tequila and Smirnoff vodka.

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At 9.3 million cases a year in the U.S., tequila is well behind vodka at 45.9 million and rum at 21.8 million, but it's gaining on those two other spirits.

FORBES: Mexican Invasion

Unlike vodka, which can be made in a day anywhere in the world, tequila has acquired the mystique of its geography and its two-and-a-half-century-old traditions.

FORBES: Mexican Invasion

The mass production techniques used for liquors like vodka and gin, she feels, have taken away some of the beauty of native tequila.

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