On June 20, members of its Metro District of Columbia branch confronted Homeland Security Secretary Kirstjen Nielsen at a Mexican restaurant downtown, chasing her out and making national news.
Six days later, Alexandria Ocasio-Cortez wrestled the Democratic House nomination away from Rep. Joseph Crowley, N.Y., becoming an instant political star, crisscrossing the country to boost other candidates and talking up "democratic socialism" on late-night TV.
Three days after her win, the Los Angeles City Council approved a ballot measure that would create a public bank, to replace Wall Street banks and payday loan centers with something accountable to voters - a cause that the city's two growing DSA chapters had helped to pull from obscurity.
DSA, founded in 1982 and nearly moribund before 2016, has never had more adherents or more clout. It's not a political party, although members are often asked if it is. It's not directing the Democratic Party's agenda, but rather is the most visible and well-organized force in politics for an ideology that both major parties have previously viewed with hostility.
Republicans have jumped on the socialist victories to impugn all Democrats. Democrats in the party's centrist wing have likewise been rattled, worried that the democratic socialists' prominence will define every party candidate as far left in competitive districts that are not.
"We've got to abandon a politics of anxiety that is characterized by wild-eyed proposals and instead deliver ideas and practical solutions," Sen. Christopher Coons, D-Del., said at a June conference organized by the centrist New Democrats.
To blunt the rise of an organization that calls for the abolition of capitalism, the end of prisons and a consumer boycott of Israel, opponents have either conjured historical allusions or dismissed its adherents. Ocasio-Cortez, who at 28 is likely to be the youngest member of Congress next year, has drawn the mockery of Republicans trying to tie her and her ideology to yesteryear's socialists.
Ron de Santis, a GOP gubernatorial candidate in Florida, belittled Ocasio-Cortez as "this girl . . . or whatever she is." Ocasio-Cortez volleyed back: "I am a Puerto Rican woman."
Days after he encouraged voters to side with Democrats in November, former FBI director James Comey reflected concern that embracing a socialist agenda would doom them: "Democrats, please, please don't lose your minds and rush to the socialist left."
Those sentiments have not stopped the momentum that began with the 2016 presidential campaign of Sen. Bernie Sanders, I-Vt., who called himself a democratic socialist even though he did not align with any particular group.
Candidates such as Cynthia Nixon, an actress who is running for governor of New York, are proudly identifying themselves as "democratic socialists," with a small "d," signifying that they want to replace modern capitalism with an economy driven by workers. DSA activists have become some of the most aggressive foot soldiers in politics, spending countless hours on canvassing and protests - and scoring high-profile upsets.
In two years, with strategies that merged outsider protests and electoral politics. DSA has grown from a self-reported 6,745 dues-paying members to nearly 45,000 - thousands of them just since Ocasio-Cortez's win. What had been a small network of chapters in college towns and big cities has grown to 47 states and the District of Columbia, from Honolulu to Cape Cod, Mass.
"DSA is unapologetic in saying that all of us as human beings are valuable," said Elizabeth Fielder, a Philadelphia activist who won a May primary for a safe legislative seat - one of three DSA members who won Democratic nominations that day. "In my campaign, most people we'd talked to at their doors had not had interactions with the Democratic Party. People didn't come asking them for their opinions."
The organization has grown despite - or perhaps because of - a lack of centralization or self-policing. While DSA meets every two years to work out its constitution, members, individual chapters and some DSA-backed candidates often diverge from it. The chapters have remained strong and active, many members said, for the simple reason that DSA activists were having fun. More than one DSA chapter has held a "karaoke caucus."
"When you go mess up [Mayor] Eric Garcetti's inauguration party because he refuses to designate L.A. as a sanctuary city, and you block his car from leaving, you're gonna want to hang out with the people who did that," said Josh Androsky, a member of Westside Los Angeles DSA. "If you are then willing to spend your Saturday - the precious hours you have not grinded away by capitalism - working on a political cause, hey, it turns out these dudes who are your comrades are also your friends."
All of it happens on a relatively small scale and budget. Plenty of left-wing organizations are larger; MoveOn, a left-liberal organizing force that grew out of opposition to Bill Clinton's impeachment, claims 7 million members nationwide.
Plenty of organizations have more money. A first-year DSA membership is $45, and a regular membership is $60, putting DSA's main revenue stream at a bit less than $2.5 million annually. It's exponentially larger than the budgets of the past, but for comparison, Turning Point USA - a conservative group that organizes on college campuses and distributes "Socialism Sucks" merchandise - raised $8.2 million in the last fiscal year.
At the moment, that budget pays for a website, a small national staff and plenty of literature for DSA's two major political efforts. In January, the National Political Committee - elected at last year's convention - dictated that 2018 would be spent on campaigns for "Medicare for All" and for making it easier to form and join labor unions.
"DSA isn't waiting around, having focus groups with donors, or making viral videos with the cast of 'The Big Bang Theory' and calling that activism," said Rob Delaney, an actor and comedian who has advocated for the Medicare for All campaign. "They're meeting in person, face to face, canvassing and explaining - among other things - that Americans inherently deserve single-payer health care, paid for by their taxes, and that that is workable and less expensive than the mishmash we have now."
DSA also works to win elections, vetting and endorsing candidates - 42 this year - and then throwing copious amounts of volunteer time behind them. Most of the candidates elected have won on Democratic ballots.
Lee Carter, a DSA member elected last year to Virginia's House of Delegates, said that the public's understanding of "socialism" was outdated, and didn't reflect the democratic aspects of what DSA wanted.
The "democratic" part of the movement's name was important, Carter said; the economic model he wanted to follow was not Soviet-style communism, but the corporate structures that exist in some European countries, where workers have a voting role in who leads their companies.
"When [bosses] have to run for election themselves, there are things they'd never do, like ship their jobs overseas to benefit investors," he said.
In recent weeks, DSA's "direct actions" have courted more controversy than any of their economic stances. During the fight against repealing the Affordable Care Act, DSA chapters had often organized protests and sit-ins of Republicans who wouldn't oppose repeal. The tumult over family separation led to even louder protests - of Nielsen, of White House adviser Stephen Miller and of Senate Majority Leader Mitch McConnell, R-Ky.
After members of the Louisville DSA chapter heckled him about the Trump administration's family separation policies, shouting, "Where are the babies?" as he pushed toward a waiting sport-utility vehicle, McConnell denounced them and asked if they were driving the Democratic Party's agenda.
"The self-described socialists who confronted me proudly admitted that they are not concerned with persuasion or having a discussion about public policy," McConnell wrote in a column for the Louisville Courier-Journal. "They are only interested in intimidation."
According to DSA organizers, such protests are a necessary complement to elections. Jacquelyn Smith, a DSA member who helped with Carter's election and with some of the Washington protests, said that both build solidarity with other left-wing movements.
"It's important for a socialist organization to do both," Smith said. "If you're taking direct action against a crappy politician, replacing them is a natural next step."
It is the inside game - trying to elect politicians - that has set DSA apart from other socialist entities. In every city with a DSA chapter, canvassers have been knocking on doors to built support for an eventual Medicare for All bill - something that would not be possible until and unless a Democrat takes back the White House.
There's not much mystery about whom DSA members want to fulfill that role. In 2015, the organization officially endorsed Sanders for president, a decision that sparked its surge of relevance. Since the start of the year, the greater Sanders organization has hired some of DSA's best-known activists, starting with David Duhalde, a District-based organizer who left the group to become field organizer for Our Revolution, Sanders's political operation.
In the short term, DSA members areworking to make the "socialist" label as sellable to as many people as possible. With a laugh, Carter remembers how Republicans in his race sent voters more than 10,000 pieces of mail that placed his face next to those of Karl Marx and Vladimir Lenin.
"If you're to the left of Barry Goldwater, they're going to call you Joseph Stalin," Carter said. "Republicans thought that was a winning issue for them. They whipped themselves into a frenzy of red-baiting. Here's hoping they keep going until 2019. Calling everyone in the world a commie doesn't work for them."
Earlier this month, at a rally in Pittsburgh organized by Sanders, the two local DSA candidates who'd won Democratic primaries took the stage to share their lessons. Sara Innamorato informed the crowd that Republicans were compiling a "list" - shades of the McCarthy era - to hang the socialist label around other Democrats.
"Instead of fighting for issues that impact people's lives, they want to waste your money on fear and further dividing us," Innamorato said. "I'm going to make it easy for Republicans who are compiling that list. My name is Sara Innamorato - I-N-N-A-M-O-R-A-T-O. I fit it on a yard sign. Put my name on the top of that list, because I'll be the one voting down your anti-choice, anti-equality, health-care-eliminating agenda."