Belaunzaran said that Calderon, of the center-right National Action Party, was once “a fanatical defender of prohibition” but that “there’s been a change in his position.”

Once out of office Dec. 1, Calderon may be more explicit about his changing views, perhaps joining former presidents of his own country, Brazil and Colombia who’ve called for decriminalization, saying the war on drugs has been a failure.

Speaking from his modest two-room congressional office, Belaunzaran said Mexican legislators might not approve his bill but that the mood among legislators was changing even as voters remained leery.

“There’s a consensus that it’s the right time to debate the matter, to put it on the table for discussion,” he said. “Prohibition has been a tragic error.”

“I only see costs and damage, and the drug-trafficking problem today is a lot worse than when it began 100 years ago, or even 40 years ago, when Nixon coined the term ‘war on drugs,’ ” he said.

A vast majority of Mexicans don’t agree with legalization, according to a recent poll. The Parametria poll, conducted in August, found that 79 percent oppose legalization and only 19 percent approve. Four out of 10 Mexicans think violence and corruption would increase were marijuana legalized, it found.

Legislators from the Institutional Revolutionary Party (PRI, in its Spanish initials), which will take power in Mexico on Dec. 1, said they weren’t opposed to a debate but didn’t favor legalization.

"It is very interesting what happened in the last elections in the U.S., but certainly the PRI is not in favor of drug legalization, and would never lead a drive to do so,” Manuel Anorve, the deputy chief of the PRI legislative faction, told the newspaper Milenio.

Belaunzaran’s bill, if enacted, would have the Secretariat of Health “regulate production, processing, distribution, sale and use of products derived from cannabis.” Licenses would be needed for each step, from farm to store. Marijuana would be sold only to those older than 18. Marijuana cigarettes would carry a tax of 160 percent.

All tax and licensing revenue would go to the National Program for Prevention and Treatment of Addiction and Rehabilitation of Cannabis Users.