Interest groups vary greatly in size, goals, and tactics. Political scientists generally divide interest groups into two categories: economic and non-economic. (http://www.sparknotes.com/us-government-and-politics/american-government/political-parties/section1.rhtml) Interest groups have their supporters and those who oppose them, but they all have the same political power. Some believe that interest groups are a liability and also believe that they have too much power over others.