The conventional view of private campaign contributions is that they distort policy to the detriment of society. Formal models consistent with such views, however, are based on restrictive assumptions about the nature of campaigns, interest groups and policy dimensionality. This paper relaxes those assumptions and allows for informative campaigns, multiple interest groups and multiple issue dimensions. It uses analytical and computational methods to demonstrate that private campaign contributions from societally unrepresentative contributors can, under reasonable conditions, improve social welfare. Multidimensionality is important because politicians need to be responsive on salient issues to prevent opponents from raising money based on less salient issues and using the money to publicize positions on salient issues.