Afghanistan's Independent Election Commission said initial results based on 10 percent of the vote from 26 out of 34 provinces showed former opposition leader Abdullah Abdullah in the lead with 41.9 percent.
Afghan President Hamid Karzai has said the election was a "success" amid relief that attacks by Taliban fighters were fewer than feared, for a vote that will bring the first-ever democratic transfer of power in a country plagued by conflict for decades.
In a statement after voting closed, President Karzai said: "The Afghan nation today have put in practice their big Jubilee of the nation's participation in voting.
"Despite the cold and rainy weather and possible terrorist attack, our sisters and brothers nationwide took in this election and their participation is a step forward and it is a success for Afghanistan."
The Democratic presidential candidate may also have shown his cards on his choice of running mate.
The US president also shared a post on Twitter accusing Dr Anthony Fauci of misleading the public over hydroxychloroquine.
Fears over an impending second wave of coronavirus dominates Wednesday’s front pages.