Hillary Clinton, on the defensive after the FBI began reexamining her email practices, was headed to the crucial state of Florida on Saturday as her White House rival Donald Trump sought to take advantage of the latest revelation in the long-running affair.
While Clinton was targeting voters in Florida, Trump, who appeared headed for certain defeat with just 10 days left in the election, was reveling in the email bombshell and stumping for votes in the western states of Colorado and Arizona.
Clinton, the 69-year-old Democrat vying to become America's first female president, is still the frontrunner to win the November 8 election, which has seen early voting kick off in 34 of 50 US states and more than 18 million votes already cast.
But some polls indicate that the race was beginning to tighten, even before the FBI made the shock announcement on Friday that it was once again looking into Clinton's use of a private email server while secretary of state.
Clinton holds a 47 percent to 45 percent lead in the latest ABC/Washington Post survey out Saturday, a drastic fall from her 12-point lead in the same poll a week ago.
According to the Real Clear Politics average of multiple polls, Clinton still holds a 44.9 percent to 41.1 percent lead over Trump nationwide.
Trump seized upon the latest revelation concerning Clinton's emails on Friday, alleging it was proof that the former First Lady was "corrupt."
"The investigation is the biggest political scandal since Watergate, and it's everybody's hope that justice at last can be delivered," the 70-year-old billionaire told supporters at a rally Friday night in Cedar Rapids, Iowa, referring to the political scandal that felled former president Richard Nixon.
Clinton's campaign has been dogged by investigations into her use of private email, an issue that appeared put to rest in July when the Federal Bureau of Investigation recommended that no charges be filed over the affair.
That changed Friday when FBI Director James Comey told US lawmakers that new emails which "appear to be pertinent" had surfaced in connection with an unrelated case.
The thousands of new emails reportedly emerged after agents seized electronic devices used by Clinton's closest aide, Huma Abedin, and her husband, disgraced former congressman Anthony Weiner, who is under investigation over allegations he sent sexually explicit messages to a 15-year-old girl.
Clinton cried foul, demanding that Comey reveal more information about the probe, and declared herself "confident" that voters, and the FBI, would conclude that she had done nothing wrong.
"The American people deserve to get the full and complete facts immediately," she said. "We don't know the facts, which is why we are calling on the FBI to release all the information that it has."
However the amount of work required to review thousands of email messages makes it unlikely that the FBI will reach any conclusions before the election.
Clinton sought to downplay the impact on the race.
"I think people a long time ago made up their minds about the emails. I think that's factored in to what people think and now they are choosing a president," Clinton told supporters Friday in Des Moines, Iowa.
Vice President Joe Biden told CNN in an interview aired Saturday that he thought "the quicker they release the e-mails for the public to see them, the better off, and I have confidence in Hillary."
But Republicans are branding the new revelations as just the latest in a larger saga of Clinton corruption, accusing the former secretary of state and her husband, former president Bill Clinton, of repeated lies.
"We've seen it for 30 years, the zebra is not going to change its stripes. This is what we can expect out of a Clinton presidency," Sean Spicer, RNC chief strategist and communications director, told CNN Saturday.
FBI chief Comey justified his decision to notify Congress in an internal memo sent to employees Friday obtained by The Washington Post.
"Of course, we don't ordinarily tell Congress about ongoing investigations, but here I feel an obligation to do so given that I testified repeatedly in recent months that our investigation was completed," Comey said in the message, adding that he did not want to create a "misleading impression."
However The Washington Post reported Saturday that Justice Department officials had warned the FBI director that the move violated long-standing tradition not to do anything that could influence an election.
Meanwhile on Friday, Donald Trump announced that he had invested an additional $10 million in his campaign, bringing his total contributions to his presidential bid to more than $65 million. He has previously promised to spend more than $100 million on the effort.