Pop quiz: What significant quality relevant to opinion polls do the presidential elections of 1936, 1948, 1968, 1976, 1980, 1988, 1992, and 2000 all have in common?
Pop quiz: What significant quality relevant to opinion polls do the presidential elections of 1936, 1948, 1968, 1976, 1980, 1988, 1992, and 2000 all have in common?