Will the new FBI email probe cost Clinton the presidency?

After new revelations that the FBI is examining additional evidence concerning Clinton’s use of a private email server, the presidential election's outcome is suddenly looking more uncertain. The story reinforces existing perceptions of the former secretary of state: Despite her solid lead over Donald Trump on the ballot test, voters continue to harbor deep doubts about her trustworthiness. But if history is any guide, Trump may not benefit from the news as much as he hopes. According to some scholars, the October surprise doesn't always have much of an impact on the election. A new ABC News-Washington Post poll found that only 7% of Clinton supporters felt the investigation would make any difference.