Entering August, Trump trailed Biden by 7 percentage points in national polls, according to the RealClearPolitics polling average. Biden also holds an edge in nearly every swing state.

For months, Trump’s hope for a rebound in public opinion polls rested on an expectation that the coronavirus would subside by fall, and that the economy would show signs of improvement. Neither has happened, and the race has stagnated, with Biden maintaining — or even expanding — on his leads.

The one thing Trump needs most is time. “And that’s the one thing that he has none of with this calendar,” said Doug Herman, who was a lead mail strategist for Barack Obama's 2008 and 2012 campaigns.

One prominent Republican strategist, noting the dates that ballots will be sent to voters in Florida and elsewhere, declined even to talk about the accelerated timeline of this election.

“No,” he said. “It’s bad news.”

The Trump campaign recognizes the calendar squeeze: On Monday, it is launching an ad offensive that will focus on the earlier voting states.

Four years ago, Trump benefited from a longer runway with a less decisive electorate. About 13 percent of voters in 2016 said they made their decision between the candidates in the last week before the election, according to exit polls, with Trump carrying late deciders by about 3 percentage points.

But the number of undecided voters is smaller than it was in 2016, now representing about 10 percent of the electorate, according to both Democratic and Republican internal polling. And the sliver of voters who are undecided or registered third party are more likely to support Biden than Trump, according to a recent Reuters/Ipsos poll, with 61 percent saying they would support Biden if they had to choose now.

“Election Day is October 24 — 48 hours after the last debate,” Frank Luntz, the veteran Republican consultant and pollster, said in an email. “On that Sunday, people will wake up, have their coffee, go to church (or not) and make up their minds. On that day, the election is over.”

One reason Republicans worry about mail voting is that Democrats have been out-pacing them in mail ballot requests throughout the primaries and in the run-up to the general election in many states. In 2016, about 40 percent of voters cast ballots in person before Election Day or by mail, a number is expected to dramatically expand because of concerns about in-person voting amid a pandemic.

In North Carolina, nearly six times as many voters had requested absentee ballots by last week as had at the same time in 2016, according to Michael Bitzer, a political science professor at Catawba College who is tracking the requests. And the increase overwhelmingly favors Democrats, who account for more than half of all requests. Republicans made up just 14 percent of requests, according to Bitzer, down from about 36 percent in 2016.

Many of those voters will not immediately return their ballots, and it is difficult to predict when most ballots will be sent in. In a normal year in California, a populous state with a traditional 29-day mail ballot period, about half of the total mail vote typically is returned about 10 days before Election Day, said Paul Mitchell of Political Data Inc., a voter data firm used by both Republicans and Democrats in California.

Still, even a portion of the early vote could swing the election in competitive states decided by a relatively small number of votes.

In Minnesota, where Trump lost to Hillary Clinton in 2016 by only about 45,000 votes, early voting will start on Sept. 18. “If you’re talking about just winning on the margins here, and it being a close election … if you don’t have your s--- together by Sept. 18, it’s going to be harder to catch up,” said Minnesota's Democratic-Farmer-Labor Party chairman, Ken Martin.

In Arizona, where early voting starts Oct. 7, Steven Slugocki, Democratic Party chairman in the swing county of Maricopa, tells party activists that “Election Day is not Nov. 3. It’s October 7, and it goes until Nov. 3.”

He said, “I tell people all the time: Literally, you could win or lose in that first week, three weeks before Election Day.”

Republicans are scrambling to narrow Democrats’ mail voting advantage, with state and county parties appealing to voters to request mail ballots despite Trump’s rhetoric. In Minnesota, Republican phone-bankers are urging Trump supporters to request absentee ballots “so you can put more time and effort to helping our Republican candidates from President Trump and all GOP candidates up and down the ballot,” according to a call script obtained by POLITICO.

Jack Brill, acting chairman of the local Republican Party in Sarasota County, Fla., said his county party has “spent a ton of money” trying to increase Republican mail voting rates, and his family registered to vote by mail “to help the numbers.”

But Brill expects Republicans in his county will largely wait to swamp the polls on Election Day, as do party officials elsewhere. Jennifer Carnahan, chairwoman of the Minnesota Republican Party, said that while the party is making a “strong push” for absentee voting, “Election Day is still, as it stands now, the day when the majority of people vote.”

When it comes to undecided voters, it is becoming increasingly apparent to Republicans that the later the decision is made, the better. It is still possible that conditions surrounding the virus will improve, and even if they do not, Trump could damage Biden in the debates. Biden has profited from a period of the campaign in which he has largely remained secluded at his Delaware home.

Phillip Stephens, the Republican Party chairman in Robeson County, one of several North Carolina counties that shifted from supporting Barack Obama in 2012 to Trump in 2016, said that the “urgency is being felt by both sides.” Democrats want people to vote now, while Biden is still “in the basement,” he said, while Republicans need “to push a decision to Election Day as much as possible.”

But relying on Election Day voting can be hazardous. People forget to vote. Rain might diminish turnout. An outbreak of the coronavirus could scare potential voters away.

“Trump is going to dominate among Election Day voters,” said the longtime Republican pollster Glen Bolger. “But what if there’s bad weather in a part of a key state, or there’s a coronavirus outbreak and voters say, ‘Nah, I’m not going to stand in line and vote.’”

Rick Gorka, a Trump campaign spokesman, agreed that "Election Day isn't on Nov. 3. GOTV [get-out-the-vote] starts the day after Labor Day." But the Trump campaign disputes that the timeline is a problem for the president. If the election was held tomorrow, Gorka said, Trump would benefit from his large field and digital organization, which has been preparing for the general election — and making millions of door knocks and phone calls — since long before Biden became the nominee.

“What team does Joe Biden have in place to do get-out-the-vote efforts? He doesn’t have one,” Gorka said. “And voters, for the most part, don’t just show up … You have to beg, borrow, steal, annoy, persuade.”

Trump is working against a Democratic apparatus that is furiously trying to put the election out of reach before Election Day. Through the Biden-Democratic National Committee coordinated campaign, there are now hundreds of field staffers working on early voting efforts across the battleground states, a DNC official said. Priorities USA, the Biden campaign’s preferred big-money vehicle, is preparing to spend heavily on digital ads in August pushing Democratic-leaning voters without a history of voting by mail to request mail-in ballots, part of a $24 million vote-by-mail and voter mobilization program.

Patrick McHugh, Priorities’ executive director, said “Trump has a dwindling window of time” to turn the election in his favor. He put it at “about half the amount of time of the 100 days.”