In Chapter 7 of his book _The Spatial Model of Politics_ , “Norman Schofield writes “:http://www.amazon.com/Spatial-Model-Politics-Norman-Schofield/dp/0415569400:
bq. Indeed, the empirical model suggests that as the exogenous valence of the Labor Party leaders increased in the 1990s, then the party’s activists became less important. This provides an explanation why the party could become more centrist on the economic axis. On the other hand, as the valences of the leaders of the Conservative Party fell in the same period, then the influence on the party of anti-Europe activists increased. This suggests why the party adopted an anti-European Union position. While these observations are particular to Britain, they appear applicable to any polity such as the U.S., where activist support is important.
This struck me as offering some interesting insight into what is going on in the US today. Barack Obama, riding his tremendous personal popularity leading up to and following the 2008 presidential election, pulled the Democratic party in a fairly moderate direction, thus lessening the influence of Democratic activists who wanted to see the party move further to the left. Meanwhile, congressional Republicans, devoid of any strong leadership and extremely unpopular as a political force, have allowed activists (read: The Tea Party) to pull the party further to the right.
The central insight for Schofield is that parties have to balance the electoral cost of moving farther from the electoral center with the “boost” to resources they get from activists (see p.164-5). So one way of looking at the 2010 Congressional elections will be as exactly this type of trade-off: is the potential price the Republican party pays for moving too far to the right going to be offset by the “enthusiasm boost”:https://themonkeycage.org/2010/09/the_enthusiasm_gap.html that the Tea Party has supplied to potential Republican supporters? In some races, the added enthusiasm will probably carry the day; in other states (read: Delaware), it might not.