Battered by weeks of unrelenting negative media coverage, Republican presidential candidate Donald J. Trump was staring defeat in the face. He was underperforming 2012 Republican nominee Mitt Romney in nearly every key swing state, and a virtually unknown third-party challenger was threatening his prospects in Utah, a state which Republicans have not lost since 1964.
But with a one-page letter to Congress, F.B.I. director James Comey disclosed the discovery of new emails regarding Hillary Clinton’s use of a private email server during her tenure as secretary of state, upending the presidential race with only days to go before Election Day.
Mr. Comey’s revelation took Mr. Trump out of the headlines and reminded voters why they do not trust Mrs. Clinton. In a Washington Post/ABC News tracking poll taken shortly after the F.B.I.’s announcement, Mr. Trump led by nearly twenty points among independent voters. A more recent iteration of the same poll found that nearly half of voters view the Republican as better suited to combat corruption, while only 39 percent feel the same about Mrs. Clinton.
State and national polls tend to narrow in the final days of U.S. presidential elections, but the narrowing effect we have seen over the past week is not a typical statistical convergence. In one national poll, a 12-point lead for Mrs. Clinton early last week turned into a single-point edge for Mr. Trump in only seven days. Of the five most recent national polls with a calculable margin of error, no candidate maintains a statistically significant lead.
The other good news for Mr. Trump is that Hillary Clinton’s so-called “firewall”—the Democratic-leaning swing states where she has maintained a considerable advantage throughout this election—is fraying. The most recent polls of Colorado, a blue state with a rapidly growing Latino population, have placed Mr. Trump just within the margin of error. New Hampshire is also swinging his way, with some surveys released this week giving him a slight lead there.
Statistical guru Nate Silver from FiveThirtyEight thinks that New Hampshire could become the lynchpin of a narrow Trump victory. “If Clinton lost New Hampshire but won her other firewall states, each candidate would finish with 269 electoral votes, taking the election to the House of Representatives,” he wrote on Thursday night. “Or maybe not — if Clinton also lost the 2nd Congressional District of Maine, where polls show a tight race and where the demographics are unfavorable to her, Trump would win the Electoral College 270-268, probably despite losing the popular vote.”
“If Clinton lost New Hampshire but won her other firewall states, each candidate would finish with 269 electoral votes, taking the election to the House of Representatives.”
– Nate Silver, FiveThirtyEight
Mrs. Clinton is still strongly favored to win. In Mr. Silver’s model, she has about a two-in-three shot of winning the presidency, while the New York Times gives her a much better chance—over 80 percent—of defeating Mr. Trump. She still leads in enough swing states that she is better positioned to win on November 8th, though not necessarily by a statistically significant margin. And as record numbers of Americans turn to early voting and vote-by-mail ballots, late breaking developments and “October surprises” like Mr. Comey’s announcement are much less likely to produce a shift in the race significant enough to topple the long-standing frontrunner.