As Hillary Clinton's campaign struggles to move on from the controversy over her private email use, a slow progression of documents emerging from the State Department and the FBI could force the Democratic nominee to confront revelations about her past dealings until election day and beyond.

At least a half dozen media outlets and watchdog groups have sued the administration in search of records related to Clinton's time as secretary of state. Many of those lawsuits, as well as outstanding congressional requests, will produce documents that raise thorny questions about the Clinton Foundation, the speaking engagements for which she and her husband were paid and the private email server that landed her under investigation by the FBI.

The State Department has pushed back against multiple Freedom of Information Act cases in court by arguing it does not have the resources to process such a high volume of records in the short time that remains before voters select the next president.

But the thousands of pages under review for public release could prolong the scrutiny of Clinton's State Department tenure with the kind of piecemeal developments that have come to define the controversies of her candidacy.

Bill Clinton's speech schedules

The State Department has stonewalled a pair of FOIA requests for schedules related to the highly-paid speeches Bill Clinton delivered while his wife served as secretary of state.

The former president's office circulated dozens of speech schedules among Hillary Clinton's staff between 2009 and 2013, creating more than 1,000 pages of details about who wrote Bill Clinton checks and why.

But the agency is arguing that Bill Clinton's activities are not subject to disclosure because he was a private citizen during Hillary Clinton's State Department tenure, even though his activities had enough relevance to her team that they regularly ended up in official inboxes.

The State Department has released just 14 pages, most of them heavily redacted, to the Republican National Committee in a FOIA lawsuit over the records. Agency officials fought to slow the production of the remaining pages until 2018.

Politico said it recently received more than 1,000 pages of the former president's speech schedules in response to a six-year-old request, but noted most of the substantive information was "denied" in order to protect Bill Clinton's privacy.

Hillary Clinton has struggled to explain why her husband's speaking engagements shot up in frequency and price during her time in office. Bill Clinton personally pocketed $48 million from the speaking circuit in those four years alone.

Many of the special interest groups, foreign governments or corporations that invited the former president to speak were lobbying his wife's agency at the same time.

Hillary Clinton's meeting schedules

The Democratic nominee has weathered criticism for granting donors to her family's foundation special access to her State Department team.

However, the extent of the alleged influence-peddling remains unknown because the agency has yet to release most of the official schedules that Hillary Clinton maintained as secretary of state.

The State Department has so far given the Associated Press roughly one-third of Hillary Clinton's calendars through a contentious legal battle over a 2013 records request.

In its FOIA lawsuit, the Associated Press demanded all of Hillary Clinton's planning material after a review of the schedules initially provided to the news outlet found dozens of donor meetings that were omitted from her official calendar.

Trans-Pacific Partnership correspondence

Hillary Clinton's ever-shifting position on the controversial trade deal became a flashpoint between her and Sen. Bernie Sanders during the Democratic primary.

But the State Department has moved to conceal the records of her correspondence about TPP until late November — just weeks after the presidential election.

As secretary of state, Hillary Clinton referred to the nascent agreement as the "gold standard" of trade deals before disavowing that support years later while on the campaign trail.

Her internal discussions of TPP, sought in a FOIA case by International Business Times, could shed new light on the evolution of Hillary Clinton's trade stance.

Deleted emails

FBI Director James Comey testified in early July that his agents had recovered thousands of work-related emails from Hillary Clinton's server that the former secretary of state did not not provide in 2014, when she said she provided all official communications.

The State Department acknowledged Tuesday that it planned to provide the unspecified number of deleted emails to Judicial Watch, a conservative-leaning watchdog group.

An agency spokesman said State Department officials had not yet determined whether those records would be posted online or shared only with the nonprofit.

Critics have long lambasted Hillary Clinton for allowing her legal team to decide which emails she would turn over and which she would scrub from her private network, an arrangement that could have permitted her to withhold work-related records simply by deeming them personal.

Huma Abedin's emails

Hillary Clinton faced fresh scrutiny of her interactions with contributors to the Clinton Foundation last week when Judicial Watch released emails provided to the State Department by Huma Abedin, Hillary Clinton's former deputy chief of staff.

Abedin is the only other State Department aide known to have hosted communications on the "" network.

Insiders connected to Hillary Clinton, including longtime confidante Sidney Blumenthal, have provided the government with work-related emails that the former secretary of state deleted.

The batch of deleted emails could contain records that the Democratic nominee's lawyers intentionally removed from the final production.

For example, the emails made public last week revealed a series of instances in which Clinton Foundation donors sought favors from or an audience with Hillary Clinton's team in the early months of her time in office.

FBI investigative files

The FBI allowed the House Oversight and Intelligence committees to view classified documents from its year-long investigation of Hillary Clinton's private email use Tuesday amid a backlash from Democratic members on both panels.

Those records included notes from interviews with a number of witnesses, including the former secretary of state herself. Documents shared with the lawmakers were classified at the "secret" level.

Rep. Adam Schiff, the ranking Democrat on the Intelligence Community, said the FBI files served no "legitimate" oversight purposes but would likely allow Republicans to leak details from the probe that could hurt the presidential hopeful.

Comey accused Hillary Clinton and her aides of engaging in "extremely careless" communications that involved classified material. Notes and testimony from his investigation could pose further problems for the former secretary of state as she tries to characterize questions about the probe as asked and answered.