In the aftermath of the shocking results of the 2016 presidential election, we, like many Americans, were wondering what we could do to resist attacks on our values from the Trump Administration. As former congressional staffers, we wanted to empower everyday Americans with tools and knowledge to effectively lobby their members of Congress to stand up against Trump’s dangerous agenda. We had a simple theory when we began to write the Indivisible Guide to congressional advocacy: that Americans were already organizing to resist Trump. We knew that, in living rooms across the country, people were gathering, trying to answer the basic question of what to do; the Guide was designed to help answer that question.

But when we posted the 26-page Google Doc guide online in December, we never imagined it would grow into the nationwide grassroots movement it has become. IndivisibleGuide.com has been viewed around 20 million times, and nearly 6,000 groups have sprouted up to put the guide into action—an average of 13 local groups in every congressional district, with at least two in every district. Inspired and galvanized by the guide, many of these small living room get-togethers ballooned into regular meetings that packed out community centers across the country. Many local Indivisible group members have experience with organizing or politics, but many others had never so much as called their member of Congress before joining. In other words, the threat that Trump poses to their families and communities has motivated countless Americans to step out of their comfort zone and join the resistance.

As Trump’s agenda moved through Congress, the resistance was there to meet it—on both sides of the aisle. In the early weeks of the Administration, 15 Democrats voted to confirm Mike Pompeo as CIA director—a man who slanders Muslim Americans and is open to reinstating torture. In response, crowds of constituents pooled outside the offices of Democratic senators Feinstein, Klobuchar, and Schumer, among others, imploring in disbelief at their votes, asking “Why Pompeo?”

Two weeks later, during the confirmation hearings for Secretary of Education Betsy DeVos, opposition snowballed into an avalanche of calls, office visits, and protests. Senator Bob Casey’s office reported 50,000 letters and emails opposing her nomination. Senator Heidi Heitkamp noted that 95 percent of the close to 1,400 constituents who called her office about the nomination were opposed. Both senators—and every single other Democrat—voted “no” this time. Vice President Mike Pence had to cast a historic tie-breaking vote to confirm DeVos’ nomination.

When Donald Trump won the presidential election in November, the common consensus was that the first casualty of his tenure would be the Affordable Care Act. It was a reasonable assumption, given that ACA repeal had been the top priority of Republicans in Congress for seven years. And it was right.

Trumpcare was most definitely bad legislation, but bad legislation passes all the time in Washington. The defeat of this top conservative priority represented the triumph of a deep, basic truth in American democracy: the power of organized constituent power to change what has been deemed outside the realm of the politically possible. In the early months of this Congress, constituents across the country made enough noise to get their members of Congress’ attention and influence their actions.

The groundswell resistance against an ACA repeal bill that had been simmering across the country came to a boiling point during the February congressional recess. Members of Congress were met in their home districts by masses of constituents concerned with a slew of issues, from Russia’s meddling in the election to Trumpcare (as support for Obamacare had suddenly swelled). A video from Republican Senator Tom Cotton’s town hall meeting, which he held at the urging of Ozark Indivisible, went viral when two women stood up to tell Cotton how the Affordable Care Act had saved their lives and that of their families. Soon after, Cotton became an early opponent of the House bill. Those Members of Congress who refused to meet their constituents face-to-face were represented by cardboard cutouts, empty chairs, or live chickens at constituent-led town hall events across the nation.

As a result of these tireless actions, the resistance’s first major legislative victory came on March 24th, when House Speaker Paul Ryan pulled Trumpcare and declared that the ACA was still “the law of the land.” The collapse of Trumpcare was quickly diagnosed as the product of intransigence by the far-right Freedom Caucus, who felt the Republican legislation simply did not go far enough. But the reality was a bit more complicated. Organized constituent pressure in deep-red districts ensured that Trumpcare was wildly and increasingly unpopular, which had the effect of enabling lawmakers to oppose the President’s legislation from the right without political cost. That then provided them with the leverage to demand more extreme concessions, which forced so-called “moderate lawmakers” to bail on the bill as well.

But how did this happen? The members of Congress responsible for putting the final nails in the coffin of Trumpcare had all been experiencing sustained pressure from local Indivisible groups for months. Indivisible New Hope/Lambertville flooded Congressman Lance’s public events. New Jersey 11th for Change held “Fridays with Frelinghuysen” events to pressure Representative Frelinghuysen to answer to his constituents. Indivisible Lovettsville in Virginia showed up en masse to Representative Comstock’s district office to hold up signs and to share personal stories proclaiming their support for maintaining the ACA. Whether their representatives met with them or not, they made sure to get their message across.

Of course, the victory in the fight against Trumpcare was not the product of Indivisible groups working alone—it was, instead, the product of a collaborative push across the progressive movement. At the national level, Indivisible partnered with Organizing for America, Planned Parenthood, MoveOn, Protect Our Care, and other national and local organizations to fight and win this battle. If there’s one good thing we can say about Trump after months spent working against him: He’s unifying the progressive community like never before.

As we look to the future, there are two things to keep in mind. First, local action sprouted organically and has taken root not only in liberal areas, but across the country. This shows the strength of the Trump resistance. For example, in Florida’s very conservative third district, a member of Indivisible Gainesville got her congressman, Ted Yoho, to publicly change his stance on demanding that Trump release his tax returns. Over the next two years, sustained local action will be critical in shaping the environment in which Congress operates. Republicans are facing an unprecedented backlash, but resistance groups aren’t just focusing on Republicans. Voters from coast to coast are ensuring representatives of either party know their constituents are watching them, ready to hold them accountable for all the Administration’s policies that pose a danger to their communities.

Second, this wave is being driven by a deep sense of fear for our country that was triggered by the election of a profoundly dangerous and unqualified President. Activists are motivated not just by health care but by many concerns including attacks on immigrants and people of color, on women’s rights, on the environment, and on our social safety net. As a result, the progressive political world has widely recognized that this moment calls for unity; that feeling is recognized, and amplified, across the country by Americans who are standing up and making their voices heard, together.

And this brings us to the most important question: What’s next? What started as a movement to resist Trump has the power to become the sort of nationwide progressive civic engagement, community-level infrastructure that has been missing in many communities for a long time. What we are seeing are constituents who are getting involved for the first time, committed to sustaining their newfound constituent power. Local Indivisible groups are rallying communities to defend against dangerous legislation, change policy outcomes, and turn out votes for candidates who will represent them—and not Donald Trump.

Just as we ended the Guide, so we end today with this certainty: Together, we will win.