Labor advocates are pushing the Senate to recognize staff unions, in the hopes of kick-starting progress in the chamber now that their House organizing efforts have stalled under Republican control.

The Congressional Workers Union sent a letter Thursday to Senate Majority Leader Charles E. Schumer, Majority Whip Richard J. Durbin, Rules and Administration Chairwoman Amy Klobuchar and Health, Education, Labor and Pensions Chairman Bernie Sanders, demanding a vote by the end of the month on a resolution authorizing Senate offices to unionize.

“Many of us write and work tirelessly to advance the very laws that protect and promote every worker’s right to organize,” the group wrote. “We deserve those same rights — the institution of Congress should not be above the very laws it creates.”

If the Senate fails to act by March, a CWU spokesperson said, two Senate offices stand ready to ask for voluntary recognition instead.

Under Democratic control, the House started allowing offices to unionize last year by adopting regulations promulgated by the Office of Congressional Workplace Rights. The organization push came amid a larger demand among Hill aides for better pay and working conditions. By the end of the year, staffers for 14 House Democrats had filed union petitions.

The Senate, however, never adopted its own authorizing resolution to implement the rules OCWR wrote pursuant to the Congressional Accountability Act of 1995 — a law Republicans passed to subject Congress to the same workplace laws as the private sector. While Democrats control that chamber, they would need to find Republican support to overcome the 60-vote threshold to break a filibuster.

To the extent they have discussed it, most Senate Republicans have derided the idea of staff unions. Even Charles Grassley of Iowa, who authored the CAA and penned a 1998 Harvard Law Review article arguing for its full implementation, told CQ Roll Call last year that he was undecided on a resolution.

The Senate push comes as the House organizing efforts now face open hostility under GOP control. The chamber’s new rules package purports to ban staff unions by stating that last year’s union-authorizing resolution “shall have no force or effect” in the 118th Congress.

Legal experts believe that language probably blocks House offices from forming new unions, but doesn’t dissolve those that have already formed or prevent OCWR from overseeing elections for offices that filed organizing petitions last year. Currently, there are six certified staff unions and seven that filed petitions, covering in total about 85 employees across 13 offices. (The CWU lost one office when the group’s biggest backer, Andy Levin, lost his reelection bid.)

Even if the OCWR regulations don’t apply, there’s nothing stopping a member of Congress from voluntarily recognizing a staff union and agreeing to collective bargaining.

The CWU believes that, certified or not, the more unionized offices there are, the more pressure nonunionized offices will feel. Just a few collective bargaining agreements could help set the terms for aide contracts across the Hill.