Hillary Clinton could face an FBI investigation that stretches well beyond this November’s election, casting a shadow over the presumed Democratic candidate’s campaign and raising the prospect of the second impeachment hearing against a Clinton president.

Clinton is under investigation for her use of a private email server during her time as Secretary of State. Many legal experts believe the investigation will end with the FBI recommending that the Justice Department indict Clinton, but the timing has been in question.

Now, Republican Congressman Darrell Issa, who once served as chair of the House Government Oversight Committee, said he believes it may not be resolved until after the election. Speaking to Fox News host Maria Bartiromo, Issa said he believes the nature of the investigation and the sheer volume of emails for them to pore over means it will take a very long time.

“What’s happening in the investigation is, I think, the FBI is running into a problem that there is too much to investigate,” Issa said (via the Washington Examiner). “I believe they are going to have to make a summary finding as to her violations of the National Records Act, her taking of the documents and, of course, the classified portion.”

Issa said the most complicated part of the investigation will deal with allegation that the Clinton Foundation accepted kickbacks from foreign interests in exchange for favorable deals during Hillary Clinton’s time as Secretary of State.

Despite reports several weeks ago that the FBI would be interviewing Hillary Clinton any day, the investigation has not yet reached that point. Clinton herself said this week that she has not met with investigators related to the allegations of using an unauthorized email server.

Legal storm for @hillarycHillary Clinton FBI is investigating and she is laughing. https://t.co/vV5nPU290I — Leslie Goldman (@YourEG) April 27, 2016

Clinton has said repeatedly that she is more than willing to meet with the FBI when they come calling, but they haven’t yet.

“No, no they haven’t. But, you know, back in August, we made clear that I’m happy to answer any questions that anybody might have. And I stand by that,” Clinton said in an April interview with MSNBC (via Real Clear Politics).

FBI Director James Comey has said that there is no rush to finish the investigation before it has run its course, and certainly no pressure to have it done before the Democratic National Convention this summer.

“Somebody asked me if the Democratic National Convention is a hard stop or a key date for you? Are you doing this aimed at that? And I said, no,” he said via NBC News. “We aspire to do all our investigations in two ways — well and promptly, especially investigations that are of great interest to the public. We want to do them promptly.”

There is evidence that the FBI investigation ends with a recommendation to indict, Fox News experts Catherine Herridge and Pamela K. Browne found in a story quoting legal experts. The report found that the FBI appeared headed toward indictment, especially with the move in March to extradite the Romanian hacker known as “Gufficer,” who first revealed Clinton’s unsecured email server.

The hacker, whose real name is Marcel Lehel Lazar, is seen as a key part of the investigation against Hillary Clinton.

“Because of the proximity to Sidney Blumenthal and the activity involving Hillary’s emails, [the timing] seems to be something beyond curious,” the report quoted Ron Hosko, former assistant director of the FBI’s Criminal Investigative Division, in reference to Guccifer’s extradition.

Hillary Clinton FBI Indictment Could Come After Clinton Given The Nomination https://t.co/wlRLL5VjDk #FeelTheBern — QuaiaVoice (@QuaiaVoice) May 4, 2016

The timing of the investigation raises the possibility that the FBI could recommend an indictment against Hillary Clinton after she has officially become the Democratic Party’s nominee, or even after she wins the presidency. That could either send the Democratic Party scrambling to find a replacement candidate or could end in another familiar scenario — new impeachment proceedings for a different President Clinton.

[Photo by Alex Wong/Getty Images]