Prejudice, Ideology and IQ

[T]he effect of lower cognitive ability on prejudice toward other races and homosexuality is mediated more or less through ideology. Coarsely, stupid people aren’t racist, stupid people are more likely to be socially conservative, and more socially conservative people are more likely to be racist.

From here (discussing Hodson G and Busseri MA, "Bright Minds and Dark Attitudes: Lower Cognitive Ability Predicts Greater Prejudice Through Right-Wing Ideology and Low Intergroup Contact," Psychol Sci. 2012 Jan 5.)