With early voting already underway in many of the states that will decide the presidency, Hillary Clinton is beginning to reap the benefits of years of Democratic efforts to target and register voters, even as Republicans steadily close their disadvantage in party registration.
The first wave of data from states like Florida and North Carolina shows preliminary signs that Clinton was building a slight edge even before the revelation that Donald Trump had bragged about sexual assault muddied the race.
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Democrats are requesting more absentee ballots in Florida than they were at this point in 2012, with increases of 50 per cent in the heavily Hispanic areas around Miami and Orlando. In North Carolina, where Mitt Romney built enough of a lead in early voting four years ago to edge out a victory over President Barack Obama, Democrats are requesting mail-in ballots in larger numbers than in 2012, while Republicans' participation is declining.
These results will have more effect than ever this year, as record numbers of people are expected to cast their votes early. So many Americans will have voted by election day - more than 40 per cent in swing states, according to the Clinton campaign - that the winner could be known before November.
But despite Clinton's growing lead in the polls, her campaign to defeat Trump with early get-out-the-vote efforts is advancing along a tenuous path.
Nowhere is the trench warfare over registration and early voting closer or more vital than in Florida. In a sign of how thin the margin of victory could be, the state Democratic Party sued the Republican governor, Rick Scott, to extend Tuesday's voter registration deadline because of the disruptions caused last week by Hurricane Matthew. On Monday, a federal judge agreed to push back the deadline by one day and set a hearing for Wednesday to consider delaying it further.
Barring a huge shake-up in other swing states, Trump will lose the race if he loses Florida. Florida Republicans have significantly narrowed a voter registration gap with Democrats, which stood at more than half a million people four years ago. As of mid-September, it had shrunk to just over 274,000. Republicans were also increasing their numbers in North Carolina, Nevada and Pennsylvania.
"We've really moved the margins in so many of these states," said Chris Young, the national field director for the Republican National Committee. "And the reality is the Democrats are out of time when it comes to voter registration. In a majority of states, they've got a week, maybe two, tops."
Typically, the last weeks before the voter registration deadline are the most fruitful for Democrats. And Robby Mook, Clinton's campaign manager, said he was confident of where they stood in Florida and other swing states.
"We are literally in the midst of the highest peak in voter registration for our campaign," he said last week during a conference call with reporters, in which he called on Scott to extend the deadline because of the storm. "President Obama definitely saw the same thing back in 2012. So we know you will see those voter rolls change, but it will take a little time."
Vote-by-mail requests among Hispanics in Florida, Mook added, are up 77 per cent. And voter registration data there backs up his assertion that they are breaking for the Democratic Party in unprecedented numbers. Since January 1, just 16 per cent of new Hispanic voters registered as Republicans. That is down significantly compared with Hispanic voters who registered before 2013: 28 per cent of them registered as Republicans, according to Daniel A. Smith, a political science professor at the University of Florida.
The Clinton campaign has undertaken an ambitious effort to find likely supporters, identifying and modelling the voting behaviour of every voter in the swing states.
Few states are expected to be closer than Florida, which Obama won by just 73,000 votes in 2012, and North Carolina, which he lost by 97,000 and where polls now show a statistical tie between Clinton and Trump.
Early indications are that the Clinton campaign's efforts in North Carolina are paying off. If Trump does not win there, his path to the 270 electoral votes needed to win the White House becomes far more complicated and uncertain - and that assumes he hangs on in Florida.
According to an analysis of early voting in North Carolina's top 10 most populous counties, conducted by Michael McDonald, an assistant professor of political science at the University of Florida, ballot requests are up 17 per cent from 2012 among registered Democrats and down 27 per cent among Republicans. This suggests that Trump's weakness in urban and suburban areas may be hurting him badly among Republicans, as many expected.
Trump needs an edge in early mail-in voting to help offset the overwhelming advantage Democrats will have once early in-person voting begins on October 20. Romney's organisation on the ground in North Carolina gave him an edge over the Obama campaign in mail-in voting in 2012, helping him carry the state.
While there is too little data to point to any conclusive early-voting trends, the Clinton campaign said it was seeing encouraging signs in other states, including in the Midwest, where Trump is hoping for a surge of blue-collar support.
In Ohio, where polls once showed Trump leading, the race has tightened recently. Absentee-ballot requests from heavily Democratic Cuyahoga County, home to Cleveland, accounted for one out of every six requests statewide, Mook said. In 2012, 41 per cent of voters in the county voted absentee, and that figure is expected to climb this year.
But the Republican National Committee's investment in building a more sophisticated voter identification and registration program has been helping the party make up for lost time. Teams have fanned out across swing states, with clipboard-carrying staff members hitting Department of Motor Vehicles lines in Las Vegas, Hispanic evangelical churches in Florida and train stations in Virginia.
This is a change from years in which the party failed to create an on-the-ground network that could compete with the one the Obama campaign began working on in 2007. Adding to the challenge, the Republican Party has had to assume the work for the Trump campaign, which has neglected to undertake the kind of voter outreach that Romney and other nominees did.
"We've both learned that you have to change the electorate," said Young, the Republican National Committee field director. "That's what Obama did so well, and that's what we are doing now."
But Republicans are not seeing any clear, heartening trends in the early voting. In Iowa, for example, ballot requests from registered Democrats are down significantly more than requests from Republicans - but after the first debate, McDonald of the University of Florida noticed that ballot requests among Republicans there fell further, something he said could be attributable to Trump's widely panned performance.
Registered Republicans in Florida are also ahead of Democrats in the number of mail-in ballots requested - but by a margin of just 81,000. In Nevada, there are almost 23,000 more registered Republicans than there were in 2012, while Democrats have added only about 4000. But Democrats still outnumber Republicans in the state, where recent polls have shown a very tight presidential race.
In Pennsylvania, Republicans have added almost 40,000 registered voters. But Democrats, who have lost almost 180,000, still have a lead of around 900,000.
The question, Republican strategists said, is whether their work to catch Democrats will take longer to come to fruition. So far, it seems the answer is yes.
"I'd rather be the one with the 900,000 advantage," said John Brabender, a longtime Republican campaign manager in Pennsylvania who ran Rick Santorum's 2012 and 2016 presidential bids.
The New York Times