Mapping the expressed ideology of the Senate candidates is interesting on its own - but we can also use this information to start thinking about the upcoming race. One of the easiest concepts to grasp is the concept of the median voter theorem. Now about 60 years old, the median voter theorem suggests that when preferences are single peaked (effectively analyzing one's choices along a single dimension), the candidate who appeals to the middle voter will win an election. This is one of the reasons why the two-major parties tend to move toward the center in a general election, as both parties are focused on the median voter. This also gives rise to what political scientists call the primary paradox (those things one does to win a primary often lead to negative outcomes in the general election); during a primary and a general election, there are two different median voters to consider.
