KABUL - Partial results from last week's election put Afghan President Hamid Karzai ahead of main rival Abdullah Abdullah, but not by enough to avoid a second round run-off in October, figures released on Wednesday showed.
With 17 percent of votes tallied, Karzai held a lead of 43 percent to 34 percent over former foreign minister Abdullah.
The results have been trickling in over the past week, leaving the country in political limbo. To avoid a run-off, a candidate must secure more than 50 percent of the vote.
The election is a major test for Karzai after eight years in power and for U.S. President Barack Obama, who has poured in thousands of extra troops as part of his new regional strategy to defeat the Taliban and stabilize Afghanistan.
In Kandahar, the country's second biggest city and the spiritual home of the Taliban, authorities raised the toll from a massive truck bomb late on Tuesday to 43 dead and 65 wounded, all civilians.
The bomb devastated a section of the town and was the worst in more than a year. It came the same day four American servicemen were killed, making 2009 the deadliest year for foreign forces since the overthrow of the Taliban in 2001.
Violence has worsened sharply this year, testing Obama's new strategy and leading to a softening of support for the war in the United States as military casualties mounted in the face a growing Taliban-led insurgency.
A Taliban spokesman denied responsibility for the Kandahar blast, which Afghanistan's Interior Ministry said was carried out with a remotely detonated bomb in a parked truck.
Election officials have warned against drawing conclusions about the final count from the small initial samples. They have promised to provide daily updates but the complete count is not due until September 3.
The results suggest a disappointing turnout of only about 5.5 million votes in a country of some 30 million people. The total number of eligible voters is not known exactly, but election authorities put it at around 15 million.
Taliban fighters had launched attacks and threatened reprisals against voters during the election, scaring many Afghans away from the polls, especially in the violent south.
More than 30,000 extra U.S. troops have landed in Afghanistan this year, most part of a package of reinforcements ordered by Obama in May in response to a growing Taliban insurgency.
More than 100,000 Western troops are now in the country, 63,000 of them Americans.
The number of foreign troops killed in Afghanistan this year now stands at 295, according to icasualties.org, a website which compiles official figures. Last year, 294 died.
The U.S. reinforcements sent by Obama, along with a British contingent already deployed in the south, have advanced deep into formerly Taliban-held territory, taking heavy casualties mainly from roadside bombs. More Western troops have died since March than in the entire period from 2001-2004.
(Additional reporting by Jonathan Burch and Peter Graff; Editing by Paul Tait)