CHARLESTON, South Carolina — As she prepares for the NBC-YouTube Democratic debate here Sunday night, Hillary Clinton finds herself somewhat on the ropes in the Democratic race, facing a once-unthinkable threat from a surprisingly strong Bernie Sanders in the early primary states of Iowa and New Hampshire.
But this seemingly tense moment for the former secretary of state is hardly the first time she has grappled with a moment that threatens to derail her candidacy. In October, she endured a grueling 11-hour hearing in from of the House Benghazi committee — a punctuation mark to months of congressional hearings and investigations on the attacks on the U.S. compound in Libya. Earlier that month, she was forced to contemplate the consequences of a new rival as Vice President Joe Biden mulled and then abandoned a presidential run. And she has stumbled in her attempts to bat away questions about her use of a private email server while heading the State Department.
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The email issue in particular remains a source of nagging headlines for the campaign — at least every four weeks. Each month, the State Department must distribute a tranche of Clinton's communication under the Freedom of Information Act. While the revelations have not included major bombshells that changed the course of the campaign, they have offered the press and the public a view into how Clinton communicated with her tight-knit group of staff.
The document dumps, some of which have occurred late at night or on holidays, have now revealed a total of 43,148 pages of correspondence, about 82 percent of the planned releases. Hundreds of the emails included information subsequently upgraded in its level of classification.
Here's a selection of some of the most revealing and newsworthy exchanges
The Night of the Benghazi Attacks
On the night of the Benghazi attacks, Clinton emailed her daughter Chelsea, writing "Two of our officers were killed in Benghazi by an Al Queda-like group: The Ambassador, whom I handpicked and a young communications officer on temporary duty w a wife and two young children. Very hard day and I fear more of the same tomorrow."
Clinton's foes seized on the secretary's attribution of the attack to an Al Qaeda group rather than to a spontaneous protest, as the Obama administration later described it.
The emails also revealed Chelsea's response to the attacks. In a message to her mother, the younger Clinton drew a parallel between the Benghazi violence and the September 11 attacks. "I am so sorry about the State Department officer killed in Libya and the ongoing precariousness in Egypt and Libya. Such anathema to us as Americans - and a painful reminder or how long it took modernism to take root in the US, after the Enlightenment, the 14th, 15th, 16th 19th amendments, removal of censorship norms and laws, etc. Heading to bed to read. A strange day here. Another bright blue beautiful chilly September 11th."
An ironic admission
When Clinton was forwarded some insider analysis from John Godfrey — one of "our most knowledgeable officers in Libya," according to an aide — the secretary of state expressed surprise that Godfrey was using a personal email address rather than a State Department-issued one.
In an email from June 17, 2011, Clinton was informed that a set of talking points had not yet been transmitted because of problems with the department's secure fax system. Clinton instructed an aide "If they can't, turn into nonpaper w no identifying heading and send nonsecure." The exchange prompted outcry from critics who said that Clinton deliberately tried to strip a document of its classified markings. Clinton said the message was "never sent" in an unsecure manner and that opponents were simply trying to make an issue out of a routine exchange of information at the agency.
Hillary Clinton learns about emojis, fax machines and NPR
The published emails are rife with exchanges in which Clinton struggles with modern technology and is attended to by patient staff members. In one, Huma Abedin tries to coach Clinton through sending a fax. In another, she asks aide Philippe Reines whether she can "get smiley faces" on her new phone and says that she's "bereft" at losing her emoji prowess. She at one point expressed distress over not being able to Google the call numbers for an NPR station in New York. And she even battled with a White House phone operator who didn't believe she was who she claimed to be.
In a revealing exchange in June 2011, Clinton friend Anne-Marie Slaughter lamented the existing email infrastructure at the State Department, offering a glimpse into why officials choose to use private accounts. "It would be a great time for someone inside or outside to make a statement/ write an op-ed that points out that State's technology is so antiquated that NO ONE uses a State-issued laptop and even high officials routinely end up using their home email accounts to be able to get their work done quickly and effectively," she wrote. Clinton - from her private email address - concurred: "I think this makes good sense. How should we proceed?"
A flood of advice from Sid Blumenthal
Clinton has long maintained that longtime friend Sid Blumenthal did not serve as an adviser to the secretary, but the email traffic shows that Blumenthal frequently flooded her with political observations , memos and information from sources in the Middle East. He offered an all-caps critique of the Obama administration's 2012 re-election strategy. In message after message, he offers advice about complicated diplomatic conundrums around the globe, many of which Clinton forwarded to top aides or prints in hard copy. In 2009, he requested a chat about "my role" within the Clinton's orbit, asking " It would be helpful if you and I speak soon to define parameters of what projects I should pursue." In one piece of advice about disgraced Gen. David Petraeus, Blumenthal forwarded on a single link to a passage from Machiavelli. That item read: "That Flatterers Should Be Shunned."
Friends in high places
After suffering a concussion, the Bon Jovi family sent their regards to the secretary of state through Chelsea. The elder Clinton's instruction to aides may qualify for the Delegation Hall of Fame: "Pls respond to Bon Jovis."
This article first appeared on NBCNews.com.