Activists nationwide have pivoted to online meetings, Slack trainings and a renewed focus on social media. “We were planning on knocking on doors and talking with people about the census, checking on their voter registration and giving them a calendar of election dates,” said Martha Shockey, 65, who founded an Indivisible group in the Atlanta suburbs. “It took a couple of weeks for us to figure out how we would do any of that work in this environment.”

Twitter, Facebook and other platforms can help sustain vital links between organizers and their communities, said Theda Skocpol, a Harvard political scientist and co-editor of “Upending American Politics: Polarizing Parties, Ideological Elites, and Citizen Activists From the Tea Party to the Anti-Trump Resistance.”

“Crises like this cause people to double down on the relationship they already have. So if there are strong ties going into a crisis, they can be adapted,” she said.

But some fear that too much online activism risks depersonalizing — or defanging — their work. “Organizing is an in-person activity,” said Liat Olenick, an elementary school science teacher who co-founded a Brooklyn-based Indivisible group that’s moved its canvassing and planned Earth Day protests online. “It’s much more challenging to put people through those activities when they’re at home alone.”

Ms. Tompkins first got involved with Sunrise at a demonstration the group organized outside Senator Chuck Schumer’s apartment. For now, though, there can be no in-person events. That may not discourage longtime organizers, but it could the uninitiated. At its height, the Sunrise Zoom call had 36 participants, a few of them new recruits. But in-the-flesh monthly meetings usually drew twice that, Mr. Bogin said.

Activists are also confronting the sense of isolation social distancing can breed. For those stressing over vulnerable loved ones, lost jobs or cabin fever, remote organizing has become therapeutic as well as strategic. This month, Sunrise NYC held a community care workshop over Zoom aimed at easing anxiety. “We’re all learning to be patient with ourselves and each other,” said Ms. Shockey, the Georgia Indivisible group founder. “Our motto is to organize with a generous spirit, and this is a time for that, for sure.”

And while normal life still seems far off, activists remain hopeful that the virus-induced holding pattern will break before November. “I kind of think of social distancing as a pressure cooker, where all of the organizing that we continue to do during this time helps to build up that pressure,” Ms. Tompkins said over Zoom.