Abdullah is seeking the presidency for the third time. He lost in 2009 and 2014.
The Afghan chief executive said at a news conference on Monday that his team would “make the new government”, Presstv Reported.
“We have the most votes in this election,” Abdullah said, adding, “The results will be announced by the IEC (Independent Election Commission), but we have the most votes. The election is not going to go to a second round.”
Abdullah also mentioned reports that “some government officials” had meddled in the election process.
Several videos on social media purport to show election workers stuffing ballots in favor of Ghani.
Zuhra Bayan Shinwari, head of the IEC complaints division, said the panel had so far received 2,569 complaints.
The IEC has yet to finish tallying the election turnout.
Abdullah’s announcement has met criticism.
Senior IEC official Habib Rahman Nang said, “No candidate has the right to declare himself the winner.”
“According to the law, it is the IEC that decides who is the winner.”
Preliminary results are not expected until October 19. Candidates need more than 50 percent of the votes to be declared outright winner, or else the top two will head for a second round in November.
The Saturday election was initially slated to take place in April, but it was twice delayed because election workers were ill-prepared, and Washington was leading a push to forge a deal with the Taliban militant group.
The election, the fourth since the Taliban was toppled in 2001, took place after peace talks between the militant group and the White House collapsed earlier this month.
Since October 2018, the Taliban’s Qatar-based political bureau has been engaged in a diplomatic process with Washington, but US President Donald Trump declared the talks “dead” on September 9, after the militant group carried out a bomb attack in the capital Kabul, where 12 people, including an American soldier, were killed.
The government had long been engaging the militant group to come to the negotiating table. The Taliban, however, considers the government illegitimate.
Kabul now says it will only consider holding talks with the Taliban after the election.