At the same time, increasing numbers of Afghans see the foreign forces as occupiers. One of the reasons is the rising number of civilian casualties in military operations.

Although the UN said militants were responsible for most of the more than 1,000 conflict-related civilian deaths in the first half of the year, foreign and Afghan troops were blamed for more than 30 percent of them.

However, Karzai does not bear sole blame for the poor state of his nation eight years after the Taliban was driven from power, said Thomas Ruttig, the co-director of the Afghanistan Analysts Network, a non-profit research group.

'The international community bears half the responsibility,' he said.

It has coordinated the reconstruction work badly, which slowed the process down, he said. Warnings that the government had to stem corruption were not enforced, he added.

The countries involved in Afghanistan have also not covered themselves in glory in combating drugs, he said.

Two years ago, Karzai complained: 'Another important issue is that there is no effective coordination among the international community. They just don't have the coordination that is required. One says one thing, and the other says the opposite. One says, 'Destroy it', the other says 'Don't'. One says, 'They do it', the other blames, 'No, they do it'. For all of this, we are held responsible.'

The international community in Afghanistan still has no unified stance on fighting the cultivation and trade of drugs, nor have the Afghans prosecuted a single drug baron, many of whom are thought to have connections in the government.

Despite broken promises and only little success, Karzai can still count on the support of many Pashtuns, the country's largest ethnic group and the one to which he belongs.

And Karzai has managed to get competing candidates with good prospects to support him. It is likely they have been promised posts in his government if he wins.

The two main challengers are not radical alternatives to the incumbent: Abdullah was earlier a member of Karzai's cabinet as was former finance minister Ashraf Ghani.

'The lack of an alternative is a big problem,' Afghanistan expert Ruttig said. 'There is a lot of evidence that Karzai will succeed.'

But Ruttig said he believes the prevailing mood favours change. If Abdullah, Ghani and the minor candidates together get enough votes to deny Karzai an absolute majority, then a second round of voting would take place.

'In the second round, it would come to a polarisation, and then how the voters will behave cannot be predicted,' Ruttig said. 'The election could still be exciting.'