M.ost of the people on Elana Hunter’s list weren’t answering the door. It was a sleepy Sunday morning in southwest Philadelphia, and Hunter had left her teenage children and bearing mother to spend her morning canvassing for Vice President Kamala Harris. House after silent house, Hunter, a 52-year old HR consultant from Philly, was undeterred. “My daughter has fewer rights than me. “What the hell was I doing sitting on the sidelines?” she says. “Later in life, she will remember that I was out doing this.” She and her canvassing partner Ikethia Daniels, who had traveled from Georgia, spent hours knocking on doors and dropping off Harris literature when nobody answered.

Finally, somebody did. The woman at the door said she supported Harris, but was confused by the early voting rules in Pennsylvania. Hunter walked her through the process and gave her the address of her polling location. As she trotted down the stairs, Hunter smiled. She believed she had converted a Harris supporter into a Harris voter.

Hunter is here because of Women Wednesdays for Harris, a weekly online meeting that grew out of the many massive Zoom consortiums thrown together in to support Harris when President Joe Biden announced he was stepping off the Democratic ticket in July. Hunter liked the Women Wednesdays calls because they were “practical and tactical.” So she stepped up to form a local action group in Philadelphia. The weekly calls, partly organized by the Democratic grassroots group Indivisible Action, were designed to “make it easy for someone like me, who cares deeply but doesn’t have a lot of time.”

In a tight election, Democrats hope that a ground game powered by people like Hunter will make the difference. While Republican Donald Trump has turned over control of the Republican National Committee to his daughter-in-law and relies partly on well-funded but untested groups like Elon Musk’s America PAC for canvassing support, the Harris campaign is leaning into the tried-and- true ground game mechanics that have boosted political campaigns for decades. Nowhere is it poised to be more important than in Pennsylvania, which both sides see as the most pivotal of the seven battleground states.

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The race will come down to a “field margin,” says Pennsylvania Governor Josh Shapiro, as he addresses a canvass kickoff of roughly 100 people in all-important Bucks County. “Of course the polls are going to show it close,” Shapiro, a Democrat, told reporters after the event. “What we have is the people you saw in the other room: an army of people going out to knock on doors, make calls, throw up a lawn sign and give permission. “We got a better ground game, we got a better captain in Kamala Harris, and we’re feeling really good.”

After Shapiro’s evasive kickoff, Democratic congressional candidate Ashley Ehasz leaves to knock doors in her Bucks County district. In a small suburban neighborhood with neat, closely spaced houses, she meets Christine Kahler, a two-time Trump voter who says she is now undecided. “I don’t know how other countries are going to deal with us with a female president,” explains Kahler, 50, who works at an afterschool program. Still, she adds, “Trump makes a joke out of himself.” She says she is 88% sure she will vote for Harris.

“We’re hearing so much more of that: somebody who was previously for Trump but he’s just burned them so much,” says Ehasz, a military veteran who is trying for the second time to unseat Republican Brian Fitzpatrick, a three-term incumbent who leads in the polls. “The enthusiasm gap is very real.”

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Donna Petrecco’s house in Bucks County is a small dot in a sea of ​​pro-Trump signs. Her neighbors have installed blow-up Trumps on their lawn and a “Lets Go Brandon” sign aimed at her kitchen window. But for several weekends in a row, Petrecco has hosted canvass launches for Harris out of her home, allowing the campaign to use it as a home base for whatever it needs. She’s had dozens of volunteers come through, many from out of state, all in an effort to swing Pennsylvania’s swingiest county towards Harris. Her home is decorated with political memorabilia, including a vintage suffragist button and a photo of Barack Obama. She has Hillary Clinton’s concession speech printed on her mantle. Harris has to win, she says, gesturing at her mantle, “because there’s no more room for another concession speech.”

A good ground game can help win margin-of-error races like this one, and even Republicans concede that the Democrats have the edge. The Harris campaign knocked on more than 700,000 Pennsylvania doors in the last week, according to a campaign official—and that’s not including the thousands more knocked by Democratic groups unaffiliated with the campaign. “We thought this would be really really close, and it is,” says one Harris campaign official. “But we have the ground game to win a very, very close race and Trump does not.”

The Harris ground game strategy is at once obvious and sophisticated. Harris has more than 2,500 staff and 358 field offices across the battleground states, including more than 475 paid staffers in Pennsylvania. Since July, more than 110,000 people have volunteered with the Harris campaign in Pennsylvania, and those volunteers have knocked on nearly 2 million doors in October alone. One third of the Pennsylvania field offices are in rural counties that Trump carried by double digits in 2020, and where Harris’ goal is to hold down Trump’s margins. At the same time, the campaign is attempting to lock down the base in urban areas through long-term relational organizing targeted to hard-to-reach voters. The campaign realizes that Democrats have long taken Black and Latino votes for granted. Now, the campaign is treating them as persuasion targets as much as mobilization targets. And it believes the path to victory goes through the suburbs, where they hope college-educated voters and women could propel the VP to victory.

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Part of the Democratic ground game advantage comes from the anti-Trump grassroots infrastructure that’s been built over the course of the last eight years. Ever since Trump’s 2016 win and the Women’s March that followed, Democrats—mostly women, often suburban, usually operating outside of a traditional campaign—have spent seven years building a volunteer network that has proven to be at once remarkably effective and surprisingly flexible. These local organizers helped Democrats win the House in 2018, plugged into the 2020 campaign to help Biden win, and helped blunt the projected “red wave” in 2022. Along the way, they helped flip state legislature seats and oust local officials. Their enthusiasm has ebbed and flowed with events—many of these activities were less enthusiastic about a Biden re-election—but the infrastructure remained intact throughout. Now, in the home stretch of a final campaign against Trump, the grassroots volunteers who have spent nearly a decade fighting him are the ones who could help Harris win the purple parts of Pennsylvania, and with them maybe the election.

One of them is Deb Paul, a Massachusetts organizer who brought 12 volunteers to Philadelphia to knock on doors for Harris. Paul got engaged with the Democratic grassroots group Indivisible after the Charlottesville rally in 2017; seven years later, she’s still at it. For her, Indivisible has become a social group as much as a political calling. “It went from an organization into a movement, and it’s built community through activism,” says Paul, 67, a former CEO of a healthcare company. “We’re doing something. We’re not just sitting around complaining.”