Everyone knows that this is a political stunt, enshrouded in a pious claim of "getting the truth." If this were a court of law, no prosecutor would even consider there to be reason for further investigation. After 13 hearings from multiple committees, they've already learned as much as they can about what went wrong and how to prevent it in the future.
No scandal was uncovered, nor is likely to be -- because there just isn't one. Republicans won't accept that, because then they lose it as a political tool. They're trying to sell the idea that the lack of evidence means that the White House is hiding something. There's every reason to believe that there just isn't anything else.
Just as in Iraq: They didn't find any WMD, because there were none.
I suspect that the Republicans even acknowledge this behind closed doors. But they've lost gay marriage and Obamacare as political rallying points for their base, so they have to come up with something else -- and this is it.
Darrel Issa has already run it into the ground. As Pelosi put it, "Issa is damaged goods. They have to move to another venue with another chairman."
This may appeal to the Republican base, but they are not a majority. Most voters are smarter than this and will see through the sham. Just as "Obamacare" crumbled as an issue for them, Benghazi may too, especially if they over-play it -- and still come up with nothing.
PS: I just thought of a great slogan for the Democrats to use:
"These are the same folks who tried to sell you Weapons of Mass Destruction as justification for invading Iraq. We all know how that turned out.".