For Hillary Clinton and Donald Trump, it's now or never.
With nine days left until the presidential election, the two campaigns have begun a ferocious battle to turn out their voters and to shape perceptions of a last-minute twist in the probe of Ms. Clinton's prior use of a private e-mail server.
James Comey, the director of the U.S. Federal Bureau of Investigation, informed lawmakers on Friday that his agency intended to review a new batch of e-mails discovered in the course of an unrelated investigation.
The move – which contravened the policy of the U.S. Justice Department not to make comments that might influence elections – threw a wrench into the final days of the presidential contest in which a victory by Ms. Clinton had been considered a near-certainty.
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Mr. Trump's campaign is working hard to turn the latest development into a game-changer. But the fresh review of e-mails is unlikely to alter Ms. Clinton's status as the favourite to win the election on Nov. 8. It could, however, complicate the task for the Democratic Party as it seeks to seize back control of the U.S. Senate in several tight races.
According to media reports, the FBI had not yet examined the e-mails in question, which were found on a laptop used by Huma Abedin, one of Ms. Clinton's closest aides. That has left both the authorities and the campaigns in the dark about whether the messages hold any significance in the earlier investigation. The probe focused on Ms. Clinton's private e-mail server while she was secretary of state and appeared to have concluded in July.
Nevertheless, Mr. Trump, the Republican nominee, seized on the FBI director's announcement as proof of his incendiary accusations that his Democratic rival had engaged in "criminal" and "corrupt" behaviour. On Sunday, Mr. Trump's campaign manager, Kellyanne Conway, told ABC News that in order for the FBI to make such an unusual move so close to the election "means there must be something there."
Ms. Clinton's campaign struck back. The FBI's announcement is "extremely puzzling" and "completely unprecedented," said Tim Kaine, Ms. Clinton's running mate, in a television appearance on Sunday. "Why would you release information that is so incomplete when you haven't even seen the material yourself? … [Mr. Comey] owes the American public more information."
The latest e-mails were found on a laptop belonging to Anthony Weiner, a disgraced former U.S. congressman who is under investigation for allegedly sending sexually explicit messages to a minor. Mr. Weiner is married to Ms. Abedin, Ms. Clinton's aide, although Ms. Abedin announced their separation in August.
Ms. Clinton spent Sunday laser-focused on voters in the battleground state of Florida. She stopped at a Miami restaurant in the morning before speaking at a predominantly black church in Fort Lauderdale. She was also scheduled to hold a rally nearby. Mr. Trump, meanwhile, was making stops in Nevada, Colorado and New Mexico.
Despite the latest controversy, the electoral map remains forbidding for Mr. Trump. In order to win the presidency, he must carry not only the traditionally Republican states where he leads, but also three major swing states – Ohio, Florida and North Carolina – plus two of three states currently leaning toward Ms. Clinton: Nevada, Colorado and Pennsylvania. He also needs to hold a state like Utah, where independent Evan McMullin is mounting a strong bid.
According to the website FiveThirtyEight, which produces an election model based on an aggregate of national and state-level polls, as of Sunday Mr. Trump had a 21-per-cent chance of winning, compared to a 79-per-cent chance for Ms. Clinton. That's Mr. Trump's best showing in the model since early October, but it still represents challenging odds for the Republican nominee.
Indeed, the election has already begun. At least 21 million Americans have cast their ballots, either in person or via mail, in early-voting operations across the country, according to the United States Elections Project. It's tricky to parse such data, since the counts don't reveal which candidate voters supported, only their party affiliation (or lack thereof).
An NBC News analysis of early-voting data through Oct. 27 found good news for Ms. Clinton: registered Democrats were outpacing registered Republicans in voting in crucial swing states like North Carolina and Ohio. Data from Florida, meanwhile, showed that the race there was neck-and-neck, an encouraging development for Mr. Trump.
In the coming days, Ms. Clinton is dispatching a series of high-powered surrogates to rev up voter turnout in key states. Senator Elizabeth Warren and Senator Bernie Sanders, both liberal firebrands, will campaign on her behalf. And President Barack Obama will return to North Carolina to urge voters to the polls. Dubbed the "checkmate state" by Mr. Kaine, Ms. Clinton's running mate, Democrats are making an all-out push to prevail there.
Mr. Trump has no similar squad of substitutes. Instead, he is relying on his running mate, Indiana Governor Mike Pence, to criss-cross the country as the Trump campaign's war chest dwindles. This week, Mr. Trump's wife, Melania, is expected to deliver a speech in the suburbs of Philadelphia, her first public address since the Republican National Convention in July.
Mr. Trump is counting on Friday's news about the review of e-mails by federal agents to resurrect his presidential prospects. It remains unclear whether these e-mails contain new information. In July, Mr. Comey of the FBI announced that Ms. Clinton's use of a private server to handle highly classified material had been "extremely careless" but the evidence did not warrant a prosecution.
Federal officials have obtained a warrant to gain access to the new batch of e-mails, law enforcement officials told several newspapers on Sunday. Some reports have suggested that many of the messages, which number in the thousands, could be duplicates of e-mails already examined by the FBI. Whatever their content, it is all but impossible that the review of the e-mails will be completed prior to election day.