There are all kinds of extremely detailed and independent studies that confirm this. I'm only posting this one which isn't that detailed. In fact I don't think you'll find a single study that shows conservatives are smarter.
I report you decide. Enjoy
Analyses of large representative samples, from both the United States and the United Kingdom, confirm this prediction. In both countries, more intelligent children are more likely to grow up to be liberals than less intelligent children. For example, among the American sample, those who identify themselves as “very liberal” in early adulthood have a mean childhood IQ of 106.4, whereas those who identify themselves as “very conservative” in early adulthood have a mean childhood IQ of 94.8.
Even though past studies show that women are more liberal than men, and blacks are more liberal than whites, the effect of childhood intelligence on adult political ideology is twice as large as the effect of either sex or race. So it appears that, as the Hypothesis predicts, more intelligent individuals are more likely to espouse the value of liberalism than less intelligent individuals, possibly because liberalism is evolutionarily novel and conservatism is evolutionarily familiar.
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