The significant changes in presidential–House election results have occurred within regions. The implications have been national in scope, but it is within regions that there were differential rates of change within House districts for presidential and House election results. The following examines these changes by region.

In tracking change within regions, it is important to note that as the changes of the 1960s began to unfold, regions began with different situations. The South witnessed the greatest change because it began as the most distinct region within the nation. In 1950 it was a region in which the minority party within the region had a very poor image. The Republican Party had little in the way of state organizations for recruiting and supporting candidates. The party had such a poor image that when the Republican national party organization made efforts to attract support within the region, it used names that did not identify the efforts as being associated with the party. In the remainder of the nation the Democrats were generally seen as being in the minority when change started, but their disadvantage was not as bad as that faced by Republicans in the South.