Mawlana Mohamed Abdullah, one of the commissioners, said they were still completing the review of result sheets from across the country and uploading the biometric data, which had stopped for days because of technical troubles. Before an initial result can be announced, fraudulent votes must be removed and some ballots may be recounted at stations under scrutiny.

At least one of President Ashraf Ghani’s main challengers, Abdullah Abdullah, has raised questions about the transparency of the process to clean up votes. A stalemate between the two men during the messy 2014 elections nearly tore the country apart before the United States negotiated a power-sharing agreement.

Another political crisis in Afghanistan would further complicate American efforts to seek an endgame to the country’s long war, with American diplomats trying to keep alive peace talks with the Taliban that President Trump called off last month.

Mr. Abdullah’s team is concerned that a large share of fraudulent votes are being entered into the database of consolidated votes. His team worries that if an initial result is inflated by fraudulent votes and shows their opponent ahead, they will lose control of the debate about who won, even if those bad votes are later discarded. And Mr. Ghani, as the incumbent, would then have a stronger position. Mr. Ghani’s camp, on the other hand, sees Mr. Abdullah as essentially priming a dispute if he loses.

“We have a strong commitment to transparency, to neutrality, and to professionalism, and for us only biometric votes are credible,” said Awrang Zeb, one of the election commissioners. “Our system and procedures are such that until the biometrically verified votes are not separated from the rest, until the clean votes are not determined, we will not be announcing any results.”