Presidential Coattails and Midterm Loss

Since the 1930s, the general pattern in U.S. congressional elections is that the party of the winning
presidential candidate gains seats in Congress in a presidential election year ("presidential coattails"), but
then loses seats in the next midterm election ("midterm loss").

This pattern has become considerably less distinct in the past few decades (except for the 1994 election),
and in both the 1998 and 2002 midterm elections the president's party actually gained a modest number of seats.

Source: Stanley, Harold W. and Richard G. Neimi (2001) Vital Statistics on American Politics, 2001-2002. Washington, D.C.: CQ Press. Updated by author