Mr Teran, 41, candidate of the nationally ruling Institutional Revolutionary Party (PRI) in Agua Prieta, even keeps his plane on the US side of the border and crosses by car at will with a special pass. His case reflects problems facing US agents uncovering what they say are strong links between Mexico's drug cartels and local, state and possibly national-government officials.
DEA agents say that, as busts shut or slowed operations in Colombia and the Caribbean, Mexican cartels filled the gaps, usually buying protection from police, the military and local officials. They say drug barons made huge inroads into the Mexican political system under the previous president, Carlos Salinas de Gortari, now disgraced and living in Ireland. His brother Raul is in jail on suspicion of drug-money laundering and ordering the murder of a political opponent.
DEA reports allege Mr Teran, who says he made his money selling satellite dishes, is part of a cocaine cartel based in the northern state of Sonora. Planeloads of Colombian cocaine land at airstrips on his ranches before being smuggled by land into Arizona, they say. Mr Teran insists he is a simple cattle farmer. There are, he notes, no wanted posters, only campaign posters around Agua Prieta. The DEA says his wealth came from laundered drug money.
Polls suggest Mr Teran will become mayor with more than half the vote. The elections will also choose a 500-member parliament, 32 senators, a Mexico City mayor, six state governors and assorted local officials.
Mr Teran is a wanted man neither in the US nor Mexico. He can be seen driving through Douglas, Arizona, across the border from Agua Prieta, where some of his brothers and sisters live and where his Cessna is parked in a hangar.
The depth of Mexico's narco-political connections became clear this year when Jesus Gutierrez Rebollo, picked by the current president, Ernesto Zedillo, to head the nation's anti-drugs agency, was held on charges of taking pay-offs from the drug baron Amado Carrillo. General Gutierrez was in charge of the Guadalajara area in 1993 when the city's cardinal, Juan Jesus Posadas, was shot at the city airport. Local authorities, from the PRI, attempted to bill the killing as accidental - that the cardinal was caught in crossfire between two drug gangs - but most Mexicans believe that the killing reflected links and disputes among government officials, the powerful church and drug lords.
The killing in Tijuana the following year of Carlos Salinas's handpicked successor as PRI candidate for the presidency, Luis Donaldo Colosio, is also believed to have stemmed from a narco-political conspiracy. A few weeks before his death Colosio had appeared to turn against Mr Salinas in a campaign speech.
Both Raul and Carlos Salinas deny drug connections. Raul earned only a civil servant's salary as an official in his brother's 1988-94 government but $100m was traced to him in Swiss and other foreign bank accounts.
He says it was lent to him by friends who wanted him to invest it for them.Reuse content