Turnout for Liberia's first democratic transfer of power in seven decades was exceptionally high, the electoral panel has suggested.
Controversy erupted after some voters were directed to the wrong polling place or were made to stand in hot sun followed by heavy rain for hours, leading the NEC to apologise for the conduct of staff who misdirected voters.
One district in northeastern Nimba will also have a re-run after a failure to open all four polling places.
"It is NEC responsibility to show voters the way in a manner that they will not make mistakes," echoed Ansu Sunny, a spokesperson for Weah's Coalition for Democratic Change (CDC), though said they did not believe the problem was of a huge magnitude.
Sirleaf, Africa's first female elected head of state, is stepping down after a maximum two six-year terms in which she steered the country away from the trauma of civil war, but, say critics, failed to tackle its poverty.
The US State Department hailed the vote as "an important step toward achieving Liberia's first peaceful transfer of power from one democratically-elected head of state to another in decades".