Afghans voted under the shadow of Taliban threats of violence Thursday to choose their next president for a nation plagued by armed insurgency, drugs, corruption and a feeble government nearly eight years after the US-led invasion. Turnout, particularly in the violent south, will be key to the vote's success - the country's second direct presidential election. Taliban militants have pledged to disrupt the vote and circulated threats that those who cast ballots will be punished. Early indications in Kabul pointed to a low initial turnout, perhaps as people assessed whether casting ballots was safe. An Associated Press reporter who visited six polling centers in the capital said he saw no lines at any of them. "Yes, we are going to vote," Abdul Rahman, 35, said as he stood 50 yards (meters) outside one polling center. He and his friends were waiting to see a line of people vote safely before casting ballots. "If anything happens to the polling center, we don't want to be too close to it." International officials have predicted an imperfect election, but expressed hope that Afghans would accept it as legitimate -a key component of President Barack Obama's war strategy. President Hamid Karzai, who has held power since the Taliban was ousted in late 2001, is favored to finish first among 36 official candidates, although a late surge by former Foreign Minister Abdullah Abdullah could force a runoff if no one wins more than 50 percent. At a high school in eastern Kabul, election workers were ready at 7 a.m., but no one was there. A 30-year-old shopkeeper whose store is about 100 yards away said he didn't see the point. "I am not voting. It won't change anything in our country," said Mohammad Tahir, 30. An AP reporter in Kandahar, the south's largest city and the Taliban spiritual birthplace, also said he saw few voters. Helicopters circled overhead in the capital as police manned extra checkpoints. In one northern Kabul neighborhood, a car with loudspeakers encouraged people to vote. Karzai, wearing his traditional purple and green striped robe, voted at 7 a.m. He dipped a finger in indelible ink - a fraud prevention measure - and held it up for the cameras. "I request from the Afghan people to come out and vote so through their vote Afghanistan will be more secure, more peaceful," Karzai said. "Vote. No violence." Preliminary results were expected to be announced in Kabul on Saturday. Violence has risen sharply in Afghanistan the last three years, and the US now has more than 60,000 forces in the country close to eight years after the US invasion following the Sept. 11 attacks of 2001. On the eve of the balloting, the US military announced the deaths of six more Americans - putting August on track to become the deadliest month for American forces since the war began. Rising death tolls underscore the urgency of establishing a strong, effective government to stem the growing Taliban insurgency. Karzai, a favorite of the Bush administration, won in 2004 with 55.4 percent of the vote, riding into office on a wave of public optimism after decades of war and ruinous Taliban rule. As the US shifted resources to the war in Iraq, Afghanistan fell into steep decline, marked by record opium poppy harvests, deepening government corruption and skyrocketing violence. Faced with growing public discontent, Karzai has sought to ensure his re-election by striking alliances with regional power brokers, naming as a running-mate a Tajik strongman whom he once fired as defense minister and welcoming home notorious Uzbek warlord Abdul Rashid Dostum, allegedly responsible in the deaths of up to 2,000 Taliban prisoners early in the Afghan war. Those figures are believed capable of delivering millions of votes among their followers, but their presence in the Karzai inner circle has raised fears in Western capitals that the president will be unable to fulfill promises to fight corruption in a second term. Voter turnout - especially in the insurgency-plagued Pashtun south - is likely to be crucial not only to Karzai's chances but also to public acceptance of the results. Karzai is widely expected to run strong among his fellow Pashtuns, the country's largest ethnic group which also forms the overwhelming majority of the Taliban. Abdullah, son of a Pashtun father and a Tajik mother, is expected to win much of his votes in the Tajik north, where security is better and turnout likely to be bigger. Abdullah, an ophthalmologist who has railed against government corruption, was a member of the US-backed alliance that overthrew the Taliban in 2001 and would be expected to maintain close ties with the West. One fear is that Abdullah's followers may charge fraud and take to the streets if Karzai claims a first-round victory without a strong southern turnout. The country has been rife with rumors of ballot stuffing, bogus registrations and trafficking in registration cards on behalf of the incumbent, allegations his campaign has denied. "It's very difficult in Afghanistan to see perfect elections," Richard Holbrooke, Obama's Afghanistan-Pakistan envoy, said during a news conference in Pakistan on Wednesday. "Nowhere in the world (is there) a perfect election. Don't expect perfect elections in Afghanistan." In the south, turnout may be affected by the Taliban campaign of intimidation - whispered threats, posted warnings and a run of headline-grabbing attacks in Kabul - aimed at frightening Afghans from going to the polls. "The Taliban control our area and they have already warned us that they will cut off our fingers or kill us if we vote," said Abdul Majid, 25, a shop owner in Ghazni city. "I don't want to vote." In Afghanistan's two most important and dangerous southern provinces - where thousands of US troops deployed this summer - more than 130 polling stations will not open, officials said. These included 107 out of 242 polling stations in Helmand province, the focus of the most recent fighting, and 17 out of 271 in Kandahar, where the Taliban Islamist movement was born. Underscoring the threat, four election workers were killed Tuesday delivering materials to a polling station in northeastern Badakhshan, a province generally considered safe. Two elections workers died in a separate incident the same day when their vehicle hit a roadside bomb in Kandahar province, officials said Wednesday. And on the eve of the voting, three gunmen described by police as Taliban militants took over a bank in Kabul. Police stormed the building and killed the three. Anthony Cordesman, a former Pentagon analyst from the Center for Strategic and International Studies, said the election "is not functional democracy by Western standards" but the important thing would be for Afghans to "feel the election was legitimate by their standards." If not, he wrote in a commentary, Afghans will "see the government as distant, corrupt, and ineffective," and empower the Taliban.