KABUL, Afghanistan — Support for President Hamid Karzai has dropped sharply since his election in 2004, with fewer than a third of Afghans supporting his re-election, according to the results of a poll released Monday.
The poll, conducted by the International Republican Institute, a nonprofit pro-democracy group affiliated with the Republican Party and financed by the American government, found that only 31 percent of Afghans said they would vote for Mr. Karzai again, far less than in 2004, when he won with 54 percent of the vote. Fewer than half — 43 percent — said that Mr. Karzai’s performance warranted re-election.
Still, he easily outpaced a dozen of the other candidates he will face Aug. 20, including Abdullah, the former foreign minister, who goes by only one name and polled 7 percent, and Ashraf Ghani, the former finance minister, who polled less than 3 percent.
A total of 3,200 Afghans were interviewed in person nationwide in May for the poll, which has a margin of sampling error of plus or minus two percentage points, said Lisa Gates, a spokeswoman for the institute.
Still, the poll results suggested that Mr. Karzai could fall short of the 50 percent needed to forestall a runoff. In 2004, he was electedin the first round.
Mr. Karzai has presided over Afghanistan since the Taliban were ousted from power after the American-led invasion in late 2001. In his early days, the Taliban were scattered and weak. But they have since regrouped, and in the first week of June mounted more attacks than at any other time since the invasion.
President Karzai has received much of the blame for the deterioration in security, though he is still widely considered the favorite to win in August. In a news conference earlier this year, he said he was not surprised that his own popularity had declined.
“Well, I have been in government for seven years,” Mr. Karzai said. “It’s natural that I would not be as popular now as I was seven years ago.”
The poll found a number of other striking changes from 2004. Five years ago, nearly 8 in 10 Afghans believed the country was moving in the right direction. Now, only 3 in 10 do.
A majority of Afghans — 52 percent — said their country was less stable than it was a year ago. Indeed, only 21 percent of Afghans said the political and security situation in their region was “peaceful and stable.”
On Monday, Gen. Stanley A. McChrystal took command of American and NATO forces in a ceremony in Kabul, saying he would focus on keeping the Afghan people safe. The Obama administration chose him to replace Gen. David D. McKiernan, saying it wanted to being “fresh eyes” to the country.
General McChrystal brings extensive experience in Special Operations, which play a large role in the fighting here. American forces have been criticized by Afghan leaders for airstrikes that have killed many civilians.
“The measure of effectiveness,” General McChrystal said, will not be the number of enemies killed, but “the number of Afghans shielded from violence.”
General McChrystal’s forces are growing by 21,000 troops ordered to Afghanistan by President Obama. They will bring the total number of American troops here to 68,000. There are about 33,000 other foreign troops here.