“We’re honored that his campaign will be the first to have a unionized workforce,” Sanders campaign manager Faiz Shakir said in an emailed statement.

The campaign agreed to recognize the union, a local of the United Food and Commercial Workers, after a majority of staff signed cards over the past week. The bargaining unit was formed with around 45 employees, according to the union, and could grow to more than 1,000 as the campaign progresses.

“We expect this will mean pay parity and transparency on the campaign, with no gender bias or harassment, and equal treatment for every worker, whether they’re in Washington, D.C., Iowa, New Hampshire, or anywhere else,” UFCW Local 400 President Mark P. Federici said in an emailed statement.

Democratic campaign workers have notched a series of unionization victories in other races. Since the start of 2018, a new union called the Campaign Workers Guild has secured collective bargaining agreements with two dozen campaigns, including last year’s successful U.S. House bids by New York’s Max Rose and New Mexico’s Deb Haaland, and the re-election of Washington Congresswoman Pramila Jayapal.

A senior adviser to Julian Castro’s presidential campaign, Jennifer Fiore, told the Daily Beast in January that the organization would support a union if its staff chose to form one.