After an aggressive campaign, three front-runners emerged: Abdullah Abdullah, who was Karzai's main rival in 2009; Ashraf Ghani Ahmadzai, a well-known academic and former World Bank official; and former Foreign Minister Zalmai Rassoul. They all expressed confidence after the vote that they would win, or at least advance to a second round, but all promised to respect official, "credible" results.
Rassoul, who critics alleged was Karzai's choice, denied he had any help from the government.
"If the election goes to the second round, we are ready to go to the second round, and if we go to the second round I am confident that we will win," he told reporters Sunday.
Fears of fraud, such as ballot box stuffing and government interference, were high after the last presidential election. This time, most of the candidates deployed thousands of observers to monitor polling centers.
The official panel overseeing complaints said people have until the end of the day Monday to report any suspect issues. So far, the Electoral Complaints Commission received 2,000 complaints ranging from polling centers running out of ballot papers, interference by election workers and government employees and in some cases by the observers themselves, spokesman Nadir Mohsini said.
Nader Nadery, executive director of the Free and Fair Election Foundation of Afghanistan, said the level of irregularities was much less than had been anticipated and the large crowds and high numbers of observers had acted as a deterrent to fraud.
"The transparency of this election was higher," he said.
Associated Press writers Rahim Faiez and Amir Shah contributed to this report.
Kim Gamel can be followed on Twitter at www.twitter.com/kimgamel.
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