Hillary Clinton is staring down the Democratic nomination, but there are two obstacles in her way: the continuing campaign of challenger Bernie Sanders and an ongoing email scandal.

A week ago, FBI agents and prosecutors found "scant evidence" that she intended to break classification rules by using a personal email server as secretary of state.

But her legal troubles are far from over.

Clinton is still facing more scrutiny from the FBI, a civil lawsuit by a conservative group, investigations led by congressional Republicans and a government-watchdog report on email practices of several former secretaries of state, according to the Wall Street Journal.

Each of those probes could throw her campaign off message, the report said.

FBI Director James Comey declined to comment this week on whether the bureau's email investigation would finish before or after the presidential election.

"In any investigation, especially one of intense public interest...we want to do it well, and we want to do it promptly. So I feel pressure to do both of those things," he told reporters at a roundtable meeting at FBI headquarters, according to WSJ. "As between the two, we will always choose 'well.' "

It's also unclear why four years' worth of emails from Bryan Pagliano, Clinton's senior information technology staffer while she was secretary of state, disappeared.

While some of his emails have been recovered from other accounts, his testimony and communications are integral to the FBI investigation because he's the person who set up the private server in the basement of her Chappaqua, N.Y., home, according to Vanity Fair.

Clinton regularly used the server and other unclassified government networks to share and receive classified email. Her private server was weakly protected, according to a Tuesday report from The New York Times.

Also on Tuesday, The Washington Post reported that top Clinton aide Cheryl Mills and her lawyer walked out of an interview with an FBI investigator after she was questions "that her lawyer and the Justice Department had agreed would be off-limits."

The ongoing scandal continues to fuel her opponents' claims that she is untrustworthy, and a Washington Post-ABC News poll in March found that 57 percent of voters said they don't think she's trustworthy.