TARAKAI, Afghanistan — A group of Taliban fighters made their announcement in the bazaar of a nearby village a few days ago, and the word spread fast: anyone caught voting in the presidential election will have his finger — the one inked for the ballot — cut off.
So in this hamlet in southern Afghanistan, a village of adobe homes surrounded by fields of corn, the local people will stay home when much of the rest of the country goes to the polls on Thursday to choose a president.
“We can’t vote. Everybody knows it,” said Hakmatullah, a farmer who, like many Afghans, has only one name. “We are farmers, and we cannot do a thing against the Taliban.”
Across the Pashtun heartland in eastern and southern Afghanistan, where Taliban insurgents hold sway in many villages, people are being warned against going to the polls.
In many of those places, conditions have been so chaotic that many Afghans have been unable to register to vote. In many areas, there will not be any polling places to go to.
The possibility of large-scale nonparticipation by the country’s Pashtuns is casting a cloud over the Afghan presidential election, which, American and other Western officials here believe, needs to be seen as legitimate by ordinary Afghans for the next government to exercise real authority over the next five years.
Doubts about Pashtun participation are particularly injecting uncertainty into the campaign of the incumbent, Hamid Karzai. Five years ago, Mr. Karzai rode to an election victory on a wave of support from his fellow Pashtuns, who make up about 40 percent of Afghanistan’s population.
Polls show that Mr. Karzai is leading the other candidates. But those predictions could be overturned if a large number of Pashtuns stay away from the polls.
The threats against the local population in villages like Tarakai show a change in the Taliban’s tactics from previous years. Five years ago, the insurgents largely allowed voting to go forward. At the time, Afghan and American officials believed that the prospect of voting was so popular among ordinary Afghans that Taliban commanders decided that opposing it could set off a backlash.
But things are different now. The Taliban have surged in strength since 2005. Mr. Karzai, though he is the leading candidate, is vastly more unpopular than he was then. As a result, Taliban leaders are actively trying to disrupt the candidates’ campaigns and preparations for the vote.
“Afghans must boycott the deceitful American project and head for the trenches of holy war,” said a communiqué released by the Taliban leadership last month. “The holy warriors have to defeat this evil project, carry out operations against enemy centers, prevent people from participating in elections, and block all major and minor roads before Election Day.”
In other messages released since then, Taliban insurgents have claimed responsibility for killing campaign workers for Mr. Karzai and Abdullah Abdullah, another major candidate, in provinces across the country.
In Tarakai, a village of about 50 families, some local men gathered outside their homes when a group of American Marines approached on foot. Some 10,000 Marines, sent here by President Obama, have fanned out across Helmand Province over the past six weeks and are pressing an offensive against Taliban insurgents.
The local men appeared relaxed and friendly in the presence of the Marines. But they said they were too frightened of the Taliban to go to the polls on Thursday and doubtful that the Marines could protect them. The Americans stationed here, part of the Second Battalion, Eighth Marines, have been in combat with Taliban insurgents nearly every day since arriving in the area on July 2.
“When you leave here, the Taliban will come at night and ask us why we were talking to you,” a villager named Abdul Razzaq said. “If we cooperate, they would kill us.”
Even if the villagers in Tarakai were inclined to cast ballots, they would be hard-pressed to do so. The nearest polling station will be in the town of Garmsir, the capital of the district of the same name, 12 miles up an unpaved road pockmarked with craters from homemade bombs. Afghan officials considered setting up polling places across Helmand Province, but concluded that many areas were not safe enough. In the district, which straddles the Helmand River, there will be seven voting precincts in the capital, but none elsewhere.
“It’s too insecure in those places,” said Lt. Col. Christian Cabaniss, the Second Battalion’s commander.
What is more, anarchic conditions have prevented many Afghans from registering to vote. Earlier in the year, when the government was registering voters, there were no Marines in the area and the Taliban were in control. The Afghan Independent Election Commission sent no officials to the area to sign up potential voters.
In their six weeks here, the Marines have succeeded in chasing many Taliban fighters from the area. But the Taliban, and the fears of them, linger.
One farmer said the Taliban regularly imposed a tax on the crops in the area.
Another, an elderly man with a long white beard, said the Taliban fighters were sure to deal harshly with people who talked to the Americans.
“We’re afraid you’re going to leave this place after a few months,” he told First Lt. Patrick Nevins, an officer from Chapel Hill, N.C., who led the Marine unit into Tarakai.
“I promise you,” Lieutenant Nevins said, “we will be here when the weather gets cold, and when it gets hot again.”
The Marines walked back to their base, and the Afghans back into their homes.