According to a new Gallup poll, unions have surged in popularity in recent years. Since 2008, the approval of organized labor grew by ten percentage points to 58% after reaching historic lows at the onset of the Great Recession. Remarkably, approval for unions grew 5% in the last year alone. At a time when labor laws are becoming increasingly hostile towards organizing and the number of unionized workers is declining, Americans have started to view unions more favorably. Even noted critics of labor are changing their minds. It is worth reflecting on what has spurred this shift in public opinion.

One of the reasons is that people are realizing that unions play an important role in sustaining America’s middle class. A study in the American Sociological Review found that the decline in union density may account for a third of the increase in wage inequality among men and a fifth of the increased inequality among women since 1973. This chart from the Economic Policy Institute clearly demonstrates how unions redistribute wealth towards the bottom 90% of earners. Now that income inequality is a cause of concern for most Americans, unions seem more appealing.

Another probable cause of the popularity boost is the conscious decision to fight for programs that benefit the common good. With fewer resources than ever, unions are succeeding in raising wages for non-unionized employees at Walmart and fast food restaurants across the country. Moreover, unions in the public sector are leveraging their collective bargaining rights to safeguard vital public services and ensure that children receive the education that they deserve. In St. Paul, teachers partnered with parents to win major improvements for a school system that predominantly serves students from low-income families of color. When labor goes to the mat for society as a whole, it gains the support of community allies and positions itself to win the fight. This is the philosophy of Bargaining for the Common Good, and it has likely contributed to unions’ improving image.

What remains to be seen is whether organized labor will continue to invest in the type of campaigns that have reversed its perception problem. These efforts are costly and can cause internal tension. Some unions are already rethinking their role. Unions should keep in mind that Gallup’s study also found that six-out-of-ten Americans want unions to maintain or increase their influence in politics. That influence isn’t limited to electoral politics, but includes the advocacy and mobilization that characterize the Fight for 15 and Bargaining for the Common Good movements. Our country needs unions to do more than exist; it needs them to be a transformational force for justice in our communities.