Morales won last month's vote with a lead of just over 10 points over Carlos Mesa, his nearest rival, giving him an outright win.
The victory, avoiding a second-round runoff vote, was marred by a near 24-hour halt in the count, which, when resumed, showed a sharp and unexplained shift in Morales' favour.
The Organisation of American States (OAS) is doing a count audit, expected to be completed before the middle of the month.
It raised concerns after the count was halted and has recommended a second-round vote.
But critics of Morales have not been placated by the audit, calling for Morales to step down.