What was the last election of the 5th party system/first election of the 6th?

[Orser67]

Accepting the first four party systems as being from about 1792-1826, 1828-1854, 1856-1894, and 1896-1930, I think there are three reasonable dates for the end of the fifth party system and start of the sixth.

1966/68: This date would fit in best with the 25-40 years cycles of previous party system, and focuses on a few factors: the start of a period of Republican dominance of the presidency, the end of the Solid South (1966 marked the first time that Republicans really became competitive in congressional races in the South, and 1968 marked the first time since Reconstruction that the South voted en masse against the Democratic presidential candidate), the end of a period of liberal legislation (New Deal+Great Society), and the end of the Warren Court (the Supreme Court tends to be a trailing indicator of party systems). On the other hand, Democrats continued to dominate Congress and there actually was a fair amount of important, left-leaning legislation passed in the 1970s.

1980: This date would focus on the rise of Reagan and the country's turn to the right (especially on economic issues) after 1980. Republicans continued to grow stronger in the South (while Democratic strength shifted to other regions), and Republicans took control of a chamber of Congress for the first time since the 1950s.

1992/1994: This set of dates would look the least like other realignments (which generally saw either the establishment of new parties or a disastrous midterm for the party in power followed by their loss of the presidency in the following election), but also probably best reflects the current composition of both parties. Democrats have won the popular vote in 6 of 7 presidential elections since 1992 (inclusive), but Republicans have generally been the stronger party in Congress since 1994. The year saw massive Republicans gains in the South, possibly marking the election where Republicans became the stronger party in the South (outside of presidential elections). Gingrich's election as Speaker lurched Republicans further to the right and marked the start of a new era of polarization in Congress.