The conversation, he noticed, had turned again.

Emotional Testimony

The Council meeting on Oct. 15 started with public testimony that lasted more than seven hours.

Again, Mr. Ilagan found himself touched by the emotion of the crowd. A mother brought her 8-year-old to testify. Mr. Brewer, the eco-hostel owner, was in the audience with his wife, who is deaf, signing so she could follow the debate. Invoking the Hawaiian word for “land,” several speakers — not necessarily of Hawaiian descent — begged for “our aina” to be preserved. “Our island can be the uncontaminated seedbed for the world,” one said.

Those in favor of the bill outnumbered those opposed by more than five to one.

Lukas Kambic, a biology major at the University of Hawaii at Hilo, sought to use his own experience to counter the anecdotes others voiced that night. “My mom ate organic food exclusively and did yoga all the time, and she died of a brain aneurysm,” Mr. Kambic said. “According to the logic of people here, she was killed by organic food and yoga.”

The room was silent.

Knowing that the final vote on the ban was yet to come, Mr. Ilagan voted “no” after the hearing. Then nearly 1,000 people quickly signed a petition demanding that he change his vote at the final hearing, scheduled for Nov. 18. For the first time in his career as councilman, he began to consider voting “kanalua” — yes, with reservation.

In early November, he sought to escape with a friend to a condo in Kona, only to be accosted at the pool by a voter demanding answers.

And on Nov. 14, Mr. Brewer, the veteran who runs an eco-hostel, visited him in his office. They discussed Mr. Brewer’s conviction that cross-pollination by G.M.O.s would do unknown harm to the environment and detract from the island’s image.

“We need all the votes we can get to override” a possible veto by the mayor, Mr. Brewer said. “Do you think you can vote for this bill, Greggor?”