Sen. Diane Feinstein, D-Calif., said she disagreed with an exhaustive report of the incident, which killed U.S. Ambassador Christopher Stevens and three CIA contractors, published in the New York Times late last year, that the incident was not tied to al-Qaida.
The Times report suggested the 2012 attack was the work of Libyan extremist group Ansar al-Sharia, not al-Qaida, and was fueled in large part by anger over an anti-Muslim Internet video that had gone viral in the days before the incident.
The Obama administration offered that motive in the initial days after the attack but came under intense criticism after it was learned Stevens had requested additional security in the months prior to his death, noting increased anti-American sentiments in some elements of the rebel groups that had fought against former dictator Moammar Gadhafi.
"It doesn't jibe with me," Feinstein said of the Times' account of the attack.
She noted Ansar al-Sharia has closer ties to al-Qaida affiliates in Africa.
The incident is likely to be a top foreign policy topic in this year's midterm elections and could be a significant one in the 2016 presidential campaign, especially if Hillary Clinton, who was secretary of state at the time of the attack, chooses to run, The Hill reported Tuesday.