ROSWELL, Georgia — On a sunny Sunday in mid-February, Karley Barber, 54, spends her morning and afternoon going door to door for Jon Ossoff, the leading Democrat running for the Georgia House seat vacated by former Rep. Tom Price, Donald Trump’s health and human services secretary.

Clipboard in hand, she laughs nervously as she marches up the steep gravel path to the first house on her list. She raps twice on the wood door frame, and shivers with a nervous jitter as someone inside approaches.

“I’ve never done this! What if they slam the door in my face?” says Barber, a government contractor with the Centers for Disease Control and Prevention.

More than 7,000 people have already volunteered for Ossoff’s campaign, and he has raised more than $3 million — unprecedented numbers for the congressional district.

The April 18 special election in Georgia’s Sixth Congressional District is Democrats’ first chance to eat into Republicans’ House majority — and potentially preview the 2018 midterm elections. “Normally, a Democrat running for Price’s seat would be lucky to raise $10,000 to $20,000,” says Phil Lunney, legislative liaison for the Fulton County Democrats. “There’s been nothing like it here, at least in the 21st century.”

But the race, held in a deeply conservative district long dominated by Republicans, will also be a test of something equally vital: whether the grassroots anti-Trump activism can be translated into electoral success. Ossoff’s race is offering a test run for whether the outpouring of energy in the streets can be harnessed by the Democratic Party, or if it will prove beyond the grasp of its politicians.

Barber’s very presence gives Democrats reason for optimism. This isn’t just her first time going canvassing for a candidate: She’s never even voted in a midterm election before. Her husband is a fervent Donald Trump supporter. Most of her friends in suburban Atlanta’s East Cobb neighborhood are Republicans. “I’d hang out with other women, and most of the time I’d keep my mouth shut because they’d just go on and on and on about how much they hate Clinton and Obama,” Barber said.

Barber said she realized she needed to do “something” after attending the Women’s March in Atlanta with her daughter, who convinced her women’s reproductive health rights were under threat from the Republican Congress. Then Barber was invited by a friend to a Facebook group called “The Liberal Moms of Roswell and East Cobb.” They keep its membership secret, in part because the community is conservative and since many of their husbands are Trump voters.

And though it’s her first time canvassing, Barber is a quick study. She hits more than 50 homes on her first day — and vows to spend her Sundays until the election keeping up the fight.

Will the Georgia Sixth special election reveal a new political realignment?

Georgia’s Sixth Congressional District is not one Democrats would normally have any business seriously contesting. Republicans have held the district, mostly composed of affluent suburbs north of Atlanta, with ease since 1979. Newt Gingrich and Sen. Johnny Isakson (R-GA) both held the seat. It’s gone red by about 30 points in each of the past five races, including in 2016, when Price won it in a landslide.

“It’s a gerrymandered, suburban, Republican district,” says Lunney, of the Georgia Democrats. “It’s a really hard place for us to win.”

But though they were crushed at the local level, something in November’s returns gave Georgia’s Democrats a cause for hope. In a dramatic swing from the past four presidential elections, Trump only won the Georgia Sixth by 1.5 points. (Romney won it by 24 points.)

In particular, the seat swung hard against Trump this year as part of Hillary Clinton’s success with the educated, upscale, and suburban voters who have not historically played as large a role in the Democratic Party’s coalition. (The median income in the Georgia Sixth is $83,000, or more than double the national average, according to census data.) The extraordinary unpopularity of House Republicans’ Obamacare repeal push — which was polling at 17 percent nationally before it collapsed — is giving Democrats further reason for optimism.

“It was the second-biggest mover in the Democrats direction of any congressional district in the country,” says Geoffrey Skelley, who studies congressional elections at the University of Virginia’s Center for Politics.

Whichever way it goes, the Georgia Sixth race will not radically alter the composition of power in Washington. Right now Republicans control 238 seats to Democrats’ 194; a one-seat switch, obviously, won’t do much to loosen that majority.

But the race could transform politicians’ perception of the political headwinds, which in turn really might have serious consequences for legislating and lawmakers’ willingness to buck Trump, according to Skelley. It’s like the long-shot Scott Brown victory in 2010, which signaled coming change to terrified, vulnerable congressional Democrats.

“The thing this race will really decide is if we’ve entered a brand new era of politics or if things will snap back to where they were previously,” Skelley says. “It’s the first big test we’re getting.”

Who is Jon Ossoff?

Ossoff’s inexperience would make an outright victory doubly surprising.

Though Ossoff is a former congressional aide and campaign manager for Rep. Hank Johnson (D-GA), who represents Atlanta, this is his first race. On the trail, he talks of staffing national security issues for Johnson, his degree from Georgetown University’s School of Foreign Service, and his master’s degree from the London School of Economics. Canvassers are also told to speak of his time as a “small-business owner” as the CEO of Insight TWI, which produces documentaries, primarily about corrupt foreign autocrats. (Ossoff was also raised in the district’s north DeKalb, where his parents still live.)

During the campaign, the Georgia GOP has tried to caricature Ossoff, 30, as something of a frat boy. A $1.1 million Star Wars–themed TV ad buy from a GOP Super PAC depicts him playing beer pong and dressing as Han Solo in an attack on his “experience.”

“Ossoff wasn’t exactly fighting against terrorism,” the ad says as someone does a keg stand in the background. “He was fighting restrictions on keg parties.”

Ossoff expresses confidence the attacks won’t get to him. "I welcome the comparison to Han Solo," he told Mic’s Andrew Joyce.

Though he has drawn the vast majority of the energy, media attention, and grassroots support of all of the Democratic candidates in the field, Ossoff has something of a surprising strategy for a leading candidate in the anti-Trump resistance: Don’t spend that much time talking about the president.

“I rarely mention his name,” Ossoff says in an interview. “Look, everyone knows what's going on in Washington right now. Folks are looking for alternatives to despair.”

Ossoff’s first order of business will be simply surviving the April 18 election. Georgia has what’s known as a “jungle primary” system, which means all the candidates from both parties get into the race at once.

If any one of them wins more than 50 percent of the vote on April 18, then that candidate takes the seat outright. The Associated Press recently captured Ossoff on an optimistic day, saying he hoped to win it “outright.” But if nobody clears the 50 percent threshold, then the two candidates who got the most votes — regardless of their party affiliation — advance to a second round that will be held in June.

As a result, Georgia Democrats have tried to encourage some of their five candidates for the seat to get out before it’s held. (The Atlanta Journal-Constitution writes Ossoff is “looking for the knockout blow.”) Meanwhile, the leading Republican candidate, Karen Handel, the Georgia GOP’s secretary of state, faces 11 other Republican candidates.

The crowded race has also fueled Democrats’ optimism in the face of the district’s firmly right-wing voting record. A shock poll out last week by zPolitics and Clout Research put Ossoff way ahead of a divided Republican field, with support from more than 40 percent of likely voters — a shockingly big lead, though not enough to avoid the runoff.

“If Republican candidates split the vote, a Democrat could conceivably sneak into the runoff,” Kennesaw State University political scientist Kerwin Swint told the Atlanta Journal-Constitution. “But that Democrat would almost surely lose the runoff. The numbers just aren’t there yet.”

The resistance gets its first big electoral test

Facing these long odds, the Ossoff campaign is testing out a message many liberals had played up during the 2016 elections: a laser-like focus on talking about pocketbook issues for the Georgia Sixth. Its informational brochures list Ossoff’s CV and background, without a mention of Trump. The script for volunteer canvassers does not mention Trump until more than halfway in.

Ossoff’s television ads talk about attracting high-tech jobs to Georgia, the need to weed out “wasteful spending,” and the possibility of finding “common ground” to fix Obamacare. (There’s only a glancing reference to holding Trump accountable at its end.) Asked to explain the energy behind his campaign, Ossoff points to his “focus” on the “local level.”

“I think we are seeing the critical importance and the amazing potential of grassroots energy at the local level,” Ossoff says. “Staying locally focused, organizing at the local level, following the lead of those who are motivated and energizing and inspiring folks at the local level — that’s the key to building momentum.”

But Ossoff’s foot soldiers say the exact opposite. In about a dozen interviews at his campaign headquarters, nearly all the volunteers stressed that the overriding reason they wanted to help Ossoff was to hurt Trump. (Political scientists have long seen a close correlation between a president’s popularity and his party’s success at the ballot in congressional elections.)

Peter Thomas, a 36-year-old software engineer, drove more than 90 minutes one Sunday in February to canvass for Ossoff’s campaign. A reporter asked if he’d have done the same for the race if Price had been appointed by President Marco Rubio or President Jeb Bush.

“Absolutely not. This is specifically about Trump. This isn’t about Democrats and Republicans. I didn’t go out to protest when Bush was president — this is all in response to Trump,” Thomas said.

Thomas added that right now he “loves” Sen. John McCain (R-AZ) because he’s “the only Republican in Congress willing to stand up to Trump.” If more congressional Republicans were like that, Thomas says, he doubts that he’d be hitting the stump for a Democratic candidate.

“The establishment Republicans can have their point of view and be reasonable, and we can debate them,” Thomas said. “But they won’t say a negative word about Trump.”

Scarlett Maier, 30, has knocked on hundreds of doors for Ossoff and vows to spend every Sunday of the six weeks leading up to the election canvassing. She said she’s recruiting as many friends as possible to join her.

Her pitch to them, in a word: Trump.

“I want enough people in Congress who are standing up to the administration — as far as balance of power goes and investigating what needs to be investigated,” she said. “I don’t think there are enough people standing up to Trump right now.”

Staffers at Ossoff’s campaign headquarters have put up a sign up in the hallway that reads, “Why do YOU want to flip the 6th?” written in big red letters.

The volunteers have written their responses on index cards and taped them to the wall.

“The 6th must be flipped BECAUSE the GOP DOES NOT represent our values,” one card says.

Adds another: “#FlipTheSixth because 45 needs to be held accountable.”

Only one of them mentions Ossoff specifically.