MEGA-PESKY for the Left! Republicans found to be brighter than Democrats
Leftists never give up asserting that they are the brightest but the research results below are well founded and are clearly against them. The findings even held among whites only. And the ardent Democrats were dumbest of all! The author is a bit apologetic about measuring mainly verbal ability but verbal ability is the best proxy for IQ as a whole so that need not detain us.
The final comment below about different types of Republicans is just a speculation. It was not examined in the research.
The differences found were slight, however so are not something for anyone to hang their hat on. The findings are primarily useful for shooting back at Leftist claims of superiority -- claims which are in fact intrinsic to Leftism. They claim to "know best"
For my previous discussions of IQ and politics see here and here and here and here
Cognitive ability and party identity in the United States
Carl (2014) analysed data from the U.S. General Social Survey (GSS), and found that individuals who identify as Republican have slightly higher verbal intelligence than those who identify as Democrat. An important qualification was that the measure of verbal intelligence used was relatively crude, namely a 10-word vocabulary test. This study examines three other measures of cognitive ability from the GSS: a test of probability knowledge, a test of verbal reasoning, and an assessment by the interviewer of how well the respondent understood the survey questions. In all three cases, individuals who identify as Republican score slightly higher than those who identify as Democrat; the unadjusted differences are 1–3 IQ points, 2–4 IQ points and 2–3 IQ points, respectively. Path analyses indicate that the associations between cognitive ability and party identity are largely but not totally accounted for by socio-economic position: individuals with higher cognitive ability tend to have better socio-economic positions, and individuals with better socio-economic positions are more likely to identify as Republican. These results are consistent with Carl's (2014) hypothesis that higher intelligence among classically liberal Republicans compensates for lower intelligence among socially conservative Republicans.