Democrat Voters have lower IQ than Independents and Republicans Combined
Research and studies have proven that Democrats are the usually the less intelligent of the 3 political parties.
Here is the data on education which is highly correlated with IQ:
Not HS Grad College Grad & Post-grad
% of Democrats 32% 15%
% of Independents 22% 18%
% of Republicans 19% 23%
Here is the data on people who earn incomes over $75,000 which is also highly correlated to IQ:
Income under $75,000 over $75,000
% of Democrats 74% 26%
% of Independents 72% 28%
% of Republicans 57% 43%
Many studies have been done on non-voters level of income and education; non-voters match independents exactly. The Republican average IQ is higher than non-voters and independents and all three are higher than the Democratic average IQ.