In a 2005 effort to reinvigorate new-member organizing efforts, seven unions split from the American Federation of Labor and Congress of Industrial Organizations (AFL-CIO) to form a new union federation, Change to Win. Using ten years of data from the National Labor Relations Board and the National Mediation Board and a difference-in-difference estimator, the author estimates the effect of Change to Win policies on whether a union won its certification election and the number and percentage of workers successfully organized. The results indicate no statistically significant difference in organizing success following Change to Win's implementation of new organizing strategies and practices, relative to the AFL-CIO.