By the end of the night, it was clear that Democrats won the House, but not by how much.

In the following days, however, new races kept being called. McBath’s victory was especially sweet. She’d become an activist after the 2012 murder of her son, Jordan Davis, by a white man who, angry over loud music, shot up a car Davis was riding in. Running in her son’s memory, she beat an incumbent with a top rating from the National Rifle Association in a largely white district.

As I write this, Democrats have flipped at least 30 House seats, and their total haul could go as high as 40. Democrats virtually wiped out the Republican Party in the Northeast, but they also won new seats in Oklahoma, Texas, Kansas and South Carolina. The party is on track to make more gains in the House than it has in any election since Watergate's aftermath. Across the country, Democrats flipped at least 333 statehouse seats, a third of all those lost over the course of Obama’s presidency.

The seeds of this success were planted after Trump’s election, when all over America scared, angry people searched for mechanisms that could constrain him. The democratic institutions that should have thwarted an authoritarian demagogue like Trump had failed, said Ezra Levin, co-founder of Indivisible, which would quickly become one of the most important Resistance groups. People were “looking around to see who or what was going to come and save them,” Levin said. “And the answer was nothing. The answer was that they had to do it themselves.”

So newly mobilized activists got to work, and quickly realized that Trump was as much a symptom of American democratic rot as its cause. In many places Democrats had neglected local organizing, allowing the party to wither at the state and local level. Throughout Barack Obama’s presidency, Republicans had built up tremendous power in the state legislatures , which they’d used to making voting harder. In the 2010 redistricting — the once-in-a-decade process of redrawing electoral maps — a significant degree of Republican gerrymandering gave the party an enduring advantage in the House of Representatives.

Indeed, it’s hard to remember now, but last year, many people thought it highly unlikely that Democrats could win the House, since Republicans had engineered a significant structural advantage. “Ultimately, Trump’s approval rating probably needs to be at or below 35 percent for the House to flip,” said The Cook Political Report.

Levin recalled a meeting last year with allies and supporters in California. He told them that because grass-roots passions had grown so intense, “I think we can take the House.” But the notion felt so wishful, he recalled, “You had to say it in hushed tones. You couldn’t say it out loud.”

Since then, Resistance energy has kept building on itself. Last year, Erin Zwiener, a children’s book author, three-time “Jeopardy” champion, and Indivisible activist in Texas, launched a campaign for state representative in her Republican-controlled district south of Austin. “Particularly at the beginning, it definitely seemed uphill,” she told me this week. But while her district had voted for Trump, the margin had been only about 4.5 percentage points, “and we were seeing folks rise up against the presidency.”