Friday's revelation that the Federal Bureau of Investigation had discovered a fresh batch of emails potentially relevant to its investigation of Hillary Clinton's private email server sent the Democratic presidential nominee's campaign clambering less than two weeks before Election Day.
An encore of the controversy that FBI Director James Comey had seemingly put to rest in July, when he announced the bureau would not recommend charges against the former US Secretary of State, could chip away at her lead over Republican opponent Donald Trump.
While a majority of all likely voters say Friday's announcement made no difference for how they intend to cast their ballots, about 34 percent say they are now less likely to back Mrs. Clinton, according to the latest Washington Post-ABC News Tracking Poll.
"The best thing this has done for Trump is change the subject from Donald Trump to Hillary Clinton, and whenever that happens he does a bit better in the polls," US Rep. Brendan Boyle (D) of Pennsylvania told Politico. "That said, will it change many people’s minds or make much of a difference? I’m skeptical."
More than anything, the polling numbers may indicate the solidification of existing viewpoints. About two-thirds of those who say the news makes them less likely to back Clinton are Republicans or independents already leaning Republican.
That being said, more than a quarter of those who report shying away from Clinton either lean Democratic (17 percent) or are independents who lean toward neither major party (9 percent), according to the Post-ABC data.
The poll shows Clinton carrying 46 percent of the electorate, practically tied with Mr. Trump's 45 percent. Libertarian candidate Gary Johnson is polling at 4 percent, and the Green Party's Dr. Jill Stein has 2 percent.
Even if the FBI's on-again, off-again investigation into Clinton's emails does not sink her campaign, its proximity to Election Day undoubtedly makes it historically significant, as The Christian Science Monitor's Mark Sappenfield reported Friday:
The timing is extraordinary. The closest recent parallel was when the FBI on Oct. 10, 1972, suggested that President Nixon’s reelection committee was linked to a campaign of political spying and sabotage. Though the scandal eventually led to Nixon’s resignation, it had no significant effect on the election one month later. Nixon won in a landslide.
But that was at a time of dramatically lower partisanship. In the current campaign, Friday’s announcement could be explosive.
The latest round of emails was discovered as the FBI investigated former Rep. Anthony Weiner (D) of New York regarding text messages to a 15-year-old girl. Mr. Weiner's estranged wife, Huma Abedin, a senior Clinton aide, shared at least one electronic device being investigated, The New York Times reported.
After discovering perhaps tens of thousands of emails, Mr. Comey informed Congress in a letter Friday that the bureau would be taking steps to "determine whether they contain classified information, as well as to assess their importance to our investigation."
Politico's Gabriel Debenedetti reported Sunday that the Clinton team has sought to portray the Democratic candidate as performing at her best under partisan attack, citing a talking points memo sent to campaign surrogates over the weekend.
"It's outrageous, though not surprising, that a Republican chairman would knowingly mislead the public and media by leaking and mischaracterizing this letter," the memo states, referring to US Rep. Jason Chaffetz (R) of Utah, chairman of the House Oversight Committee and longtime thorn in Clinton's side.
The latest polling numbers mean voter turnout could be key on Nov. 8, as ABC reported. While a majority of likely voters still expect Clinton to win, that fact could hurt her on Election Day if over-confident supporters decide not to vote.