Sanders tweeted that he was "proud" of the historical marker and, taking a page from his stump speech, tied the development to his own pro-union message.
United Food and Commercial Workers Local 400 will represent the campaign workers as Sanders, an independent USA senator from Vermont, seeks the 2020 Democratic nomination.
A majority of Sanders' campaign workers signed a union card by Friday, triggering the union's recognition, the union said. The union says that all campaign employees below the level of deputy director will be represented by the union and that negotiations for a collective bargaining agreement will begin "as soon as possible". Former Housing and Urban Development Secretary Julián Castro's campaign has signaled it would back a similar move.
The United Food & Commercial Workers Local 400 confirmed that Sanders' campaign workers were the first to win union representation. Sanders' aides said on a recent conference call that the campaign has roughly 70 paid staffers.
Mark Federici, president of Local 400, said in a statement he hoped "this breakthrough serves as a model for other presidential campaigns, as well as party committees and candidates for other offices".
Read the full report at Fox News.
While Sanders' is the first large-scale presidential campaign to unionize, the move comes in the wake of a growing wave of organization within political operations - for candidates and causes - that have for decades been effectively accepted as hard and occasionally unsafe working environments. And recently, workers on some campaigns have been pushing to unionize.