KABUL, Afghanistan — Little more than three weeks before the presidential election, problems that include insecurity and fears of fraud are raising concerns about the credibility of the race, which President Obama has called the most important event in Afghanistan this year.
With Taliban insurgents active in half the country, many Afghans remain doubtful that the Aug. 20 election will take place at all. The Taliban issued a statement last week calling for a boycott, a threat that could deter voters in much of the south, where the insurgency is strongest.
Election officials insist that the election will go ahead. But they concede that the insecurity will prevent as many as 600 polling centers, or roughly 10 percent, from opening. Western officials acknowledge that the election will be imperfect, but say they are aiming for enough credibility to satisfy both Afghans and international monitors.
Even that goal will be hard to meet. Though increasingly unpopular here and abroad, President Hamid Karzai is still the front-runner in a field of about 40 candidates, and only one, Abdullah Abdullah, a former foreign minister for Mr. Karzai, has emerged as a serious challenger. Many Afghans are convinced that foreign powers will choose the winner and fix the result.
But no matter who prevails, the multitude of problems and what is expected to be a low turnout in conflict areas are likely to reduce the next president’s mandate.
Western officials and Afghans alike worry that the election could be so flawed that many Afghans might reject the balloting and its results, with potentially dangerous consequences.
If they cannot vote because of insecurity in the south, Pashtuns, the country’s largest ethnic group and the one most closely associated with the Taliban, could become even more alienated from the government and the foreign forces backing it, political analysts say.
They also warn of Iranian-style protests and instability if the population in the north, which largely supports a change of government, feels its vote has been manipulated.
“We are worried about voter registration fraud, and we are worried about voters who will be unable to reach polling places because of insecurity,” Richard C. Holbrooke, the American special envoy, said during a visit last week. “And we are worried about the accuracy of the vote count, and we are worried about the ability of women to vote.”
Philippe Morillon, the outspoken retired French general who leads the European Union election observer mission to Afghanistan, said his top priority was to prevent fraud. “It is you who will choose your president, and we are there simply to guarantee that your choice is not betrayed,” Mr. Morillon told Afghan journalists at a news briefing in Kabul.
In an effort to speed the results and reduce the opportunity for rigging, ballots will be counted at individual polling stations. Afghan officials have said there will be a preliminary result within 48 hours, followed by a two-week period for complaints and confirmation procedures.
But Western officials say it could take longer to declare a winner, anticipating challenges from around the country’s 34 provinces, where votes will also be cast for provincial councils.
“It could be like 34 Minnesota Senate races,” one Western official said, referring to the disputed race between Al Franken and Norm Coleman, which took nearly eight months to resolve in Mr. Franken’s favor.
Other officials warn that public frustration with the war, corruption and lagging reconstruction and development is so high that many people may shun the polls.
In the south, election officials said they were expecting a turnout below 30 percent, said Abdul Qader Nurzai, head of the Afghan Independent Human Rights Commission office in Kandahar.
“The people are not that interested in the elections,” said Abdul Hadi, the election commissioner in the adjoining province of Helmand, where thousands of Marines have been deployed to regain towns from the Taliban in time for the elections.
“They voted before, and they did not see any result from that,” Mr. Hadi said. “And they don’t want to put their lives in jeopardy for one vote.” An estimated 70 percent of Afghan voters turned out for the country’s first presidential election, in October 2004.
In Helmand, in southern Afghanistan, the election will take place only in safe zones in the main towns, Mr. Hadi said. One third of districts are under Taliban control and will not be able to take part, he said. In some districts, like Kajaki, the Taliban have besieged administrative centers and will not allow civilians in to vote, he said.
In the eastern Paktika Province, which borders Pakistan’s lawless tribal areas, more than 20 percent of the voting centers will have to be moved or abandoned because of security, officials said.
Afghan election officials in the capital, Kabul, insist that voters will turn out. About 4.5 million people registered for new voting cards this year, far exceeding expectations, said Azizullah Ludin, the election commission chief.
Yet irregularities are widespread. As many as 3 million duplicate voter registration cards may be circulating among the 17 million issued, according to one election observer, who asked not to be named because of the delicacy of the subject.
Twenty percent of the new cards went to under-age boys and another 20 percent were duplicates, an Afghan election observer organization, the Free and Fair Election Foundation of Afghanistan, found in the centers it was able to monitor.
For security and cultural reasons, women’s registration has been low. Yet the number of registered women exceeded the number of registered men in some areas, indicating more irregularities. Male family members were able to obtain voting cards for women simply by providing a list of women’s names, the Afghan election monitors reported in May.
This election is unlike Afghanistan’s first presidential contest five years ago in that most balloting and monitoring is being run by Afghans, with only a small number of international advisers and observers, most prominently the 120-member mission from the European Union.
So far, the Taliban have generally refrained from specific attacks on the election process or on voters, and have even agreed to allow voting to take place in some areas.
Yet violence has increased, and in some places the Taliban are ordering communities not to take part. In a rambling statement issued Thursday through a spokesman, the Taliban leadership urged people to boycott and fighters to sabotage the process.
“We are requesting all mujahedeen to do their best to sabotage the malicious election process anywhere in Afghanistan,” it said. “They should carry out operations on enemy bases, and ban people from going to vote one day before the election.”
Richard A. Oppel Jr. contributed reporting from Kabul, and Taimoor Shah from Kandahar, Afghanistan.