Page "Political party strength in U.S. states" Paragraph 0

Throughout most of the 20th century, although the Republican and Democrat parties alternated in power at a national level, some states were so overwhelmingly dominated by one party that nomination was usually tantamount to election.

This was especially true in the Solid South, where the Republican Party was virtually nonexistent for the best part of a century, from the end of Reconstruction in the late 1870s to the 1960s.

Conversely, the New England states of Vermont, Maine, and New Hampshire were Republican bastions, as were some Midwestern states like Iowa and North Dakota.