I strongly recommend John Samples? recent policy analysis for Cato on voter turnout as a needed corrective to the conventional wisdom on the issue.
He explains that while national turnout is lower than it was in the 1950s and early 1960s, the decline was almost entirely confined to the period from 1968 to 1974, after which it has fluctuated with no obvious pattern or relationship to oft-asserted turn-offs such as negative campaigning or big-money influence.
I have discussed similar issues within North Carolina politics in some past columns.
