The U.S. should have had better security for its Embassy in Libya and we need to be determined how much was caused by congressional budget cuts.
The question is who is at fault and does it reasonable to put much of the blame on Clinton or Obama. This is not so clear. Per the organization chart of the Department of State the SOS has seventeen individuals reporting directly to her. These individuals must have the ability to work without much supervision. If they cannot, they do not belong in their position. The SOS is a diplomat and lacks sufficient time to manage this number of subordinates. Clinton cannot be blamed for this lapse and she took disciplinary action against those that were responsible.
The administration mishandled how they communicated the attack and that was definitely affected by the Presidential election. Obama deserves to be blamed for this.