WORCESTER, Mass. — Hundreds of protests were staged across the country on Thursday in the latest uproar over a repeal of rules ensuring an open internet. The drumbeat of action can in good part be traced back to a yellow Victorian house in this leafy New England city.

The home is the nerve center for Fight for the Future, a scrappy 10-person nonprofit that has helped lead the opposition to the change — even if its effort to protect so-called net neutrality has the longest of odds.

For months, the founders, Tiffiniy Cheng and Holmes Wilson, have pushed the group’s 1.8 million supporters to flood social media sites with warnings about how the change could favor big companies and hurt smaller ones. They have also supplied online tools to their followers, like one that makes it easier to call lawmakers and another to file comments directly to the Federal Communications Commission, the agency considering the repeal.

For next week, just ahead of the agency’s vote on the proposal, they have organized hundreds of internet companies to alter their websites — slowing them down, for example — to show what online experiences could be like without the rules.