Donald Trump seemed to usher in a new era of Democratic grass-roots engagement. More than four million people marched in the streets the day after his inauguration. Several thousand chapters of Indivisible, one of the biggest new “Resistance” organizations, sprung up, covering every congressional district. On the Democratic fund-raising platform ActBlue, the number of donors more than quadrupled in roughly four years, reaching 15 million during the 2020 election cycle.

But less than two years later, Democrats and national progressive organizations seem to have done very little to translate that energy into a lasting movement. What happened?

National Democratic and progressive groups together burned through the surge of liberal organizing under Mr. Trump, treating impassioned newcomers like cash cows, gig workers and stamp machines to be exploited, not a grass-roots base to be tended. Worse, research by academics and political professionals alike suggests many of the tactics they pushed to engage voters proved ineffective.

Some may even have backfired. Millions of dollars and hours were wasted in 2018 and 2020. And yet, as the party stares down a bleak midterm landscape, with abortion rights on the line, the Democratic establishment and progressive organizations alike are doubling down on the same old tactics.

For all the conflict between mainstream Democratic and progressive leaders, most share a common way of thinking about electoral politics. To the “Beltway Brain,” as we think of it, voters are data points best engaged via atomized campaigns orchestrated from afar.

The core role of supporters is to be whipped into panicked giving by messages like this one from Nancy Pelosi on April 28: “I asked — several times. Barack Obama told you the stakes. Joe Biden made an urgent plea,” she said. “I don’t know how else to say this, so I’ll be blunt: All these top Democrats would not be sounding the alarm if our democracy wasn’t in immediate danger of falling to Republicans in this election. I need 8,371 patriots to step up before time runs out, rush $15, and help me close the fund-raising gap before the End of Month Deadline in 48 hours.”