Despite the heated politics surrounding Benghazi ahead of the election, committee staffers say they expected the tone of the hearings to be civil, saying that "even Republicans on both committees generally like and respect her."

Republican Sens. Jeff Flake of Arizona and John Barasso of Wyoming both told CNN that they will have detailed questions about what went wrong in Benghazi but expect the overall tone of the hearing to be very respectful.

Democrats privately say they don't expect Republicans to be overly adversarial because they think Republicans are chagrined by being linked, fairly or unfairly, to the conspiracy theory that Clinton faked her illness to get out of testifying.

Rep. Gerald E. Connolly, a Democratic member of the House Foreign Affairs Committee, said Congress has failed to expeditiously fund State Department efforts to upgrade security at high-risk posts. He pointed a finger at House Republican leaders.

"A paucity of resources ingrains a specific culture within any organization, in this case the State Department --- namely that every purchase, every expense, must be justified in a time when the threat of even more cuts loom beyond the horizon," Connolly said in a statement released on the eve of the hearings.

Clinton is expected to detail what the State Department has done to implement 29 recommendations from the investigation by the review board in addition to a few of her own.

But officials note that she didn't wait for the review board report before appointing a State Department team to work on tightening security.

Joint teams of military special forces and diplomatic security threat analysts were sent to more than a dozen high-risk posts. A senior official was appointed to focus solely on high threat posts.

President Barack Obama ordered a review of security at all diplomatic outposts in the wake of the attack.

Despite the renewed focus on security, Clinton will stress that U.S. diplomats still need to operate in high threat environments.

"The reason that hasn't changed is that these places have a direct and vital national interest" to the United States, one official said.

Clinton also is likely to face questions about the storming of the natural gas facility last week in Algeria during which militants seized dozens of hostages. Three Americans lost their lives.

Al-Qaida in the Islamic Maghreb is believed to have had a hand in the attack. Clinton also will likely face questions about the battle against extremists in neighboring Mali.

Republicans may raise the issue of Obama's suggestion that al-Qaida was on the run following the death of Osama bin Laden in 2011.

"Clearly Benghazi and now Algeria show that is not the case," one House staffer said. "I would expect questions asking what the U.S. is going to do now."