By JOHN T. EDGE

TUCSON, Arizona - ��The problem with American hot dogs is that they��re American,�� said Tania Murillo, standing beneath a bunny-shaped pinata, as she rang up an order of tortillas at Alejandro��s Tortilla Factory.

��A ketchup-and-mustard hot dog is boring,�� continued Ms. Murillo, a high school senior. ��They��re not colorful enough. You��ve got to make them colorful, and pile on the stuff. The best hot dogs come from Sonora,�� the Mexican state immediately to the south. ��Everybody knows that.��

In Tucson more than 100 vendors, known as hotdogueros, sell Sonoranstyle hot dogs wrapped in bacon, griddled until dog and bacon fuse, garnished with a variety of condiments and toppings and stuffed into split-top rolls .

Many, like Ruiz Hot-Dogs on Sixth Avenue, work step-side carts with two-item menus of Sonoran hot dogs and soft drinks. Set in parking lots, beneath makeshift shelters, under mesquite tree arbors, these peripatetic vendors serve fast food for day laborers, craftsmen and policemen, the typical patrons of traditional hot dog stands in any American town.

Other champions of the Sonoran style, like El Guero Canelo, with two Tucson outlets, have evolved from carts into full-scale restaurants.

One Sunday afternoon, as a mariachi band played, an after-church crowd, half Anglo and half Hispanic, thronged El Guero��s outdoor dining pavilion. Babies cried. Teenagers table-hopped. And parents argued that, rather than order a second hot dog, children should fill up at the salsa bar at the back of the pavilion . Front and center on every third table was a Sonoran hot dog.

For at least the last 40 years, borderland vendors, in Tucson and elsewhere, have been refashioning the hot dog with a cloak of bacon, a clump of beans and a chop of tomatoes and onions, followed by squirts of mayonnaise, mustard and salsa verde.

In a dozen or more cities across the United States, these Mexican takes on the American hot dog are ascendant from Chicago to Denver to Los Angeles, where illegal street vendors selling so-called danger dogs to late-night crowds play hide-and-seek with the local health department.

Only in Tucson, however, do locals like Ms. Murillo cede hot dog provenance to Mexico. In Tucson, baconwrapped, Mexican-dressed hot dogs are not ascendant. They��re dominant.

A Mexican-American take on the hot dog aesthetic was relatively late to arrive. In 1940s Arizona, tamales were known, at least among speakers of colloquial English, as Mexican hot dogs. By the 1950s, true tamales, steamed corn meal filled with meat or cheese, were gaining mainstream status stateside, and American hot dogs had, more than likely, drifted south into Sonora and Baja and elsewhere.

The date at which bacon-wrapped hot dogs became known as Mexican hot dogs is unclear. From the southern side of the border, numerous Mexico City origin tales emanate, some tied to feeding crowds at wrestling matches in the 1950s, others to feeding skyscraper construction workers during the same decade. (Daniel Contreras, owner of El Guero Canelo, cites a similar time frame, but sets the action in his home state of Sonora .)

As is the case with most folk dishes, its true origins may never be pinpointed, but folkloric suppositions aside, the answer may be a matter of salesmanship:

By 1953, Oscar Mayer was running print ads, selling American consumers on the virtues of bacon-wrapped hot dogs. Perhaps Mexican consumers, inspired to emulate American dietary habits, took Oscar Mayer at its word, wrapping American-made hot dogs in American-made bacon, and claiming the resulting construction as their own.


CHRIS HINKLE FOR THE NEW YORK TIMES / A Sonoran hot dog is wrapped in bacon and includes garnishes like beans and mayonnaise.