Two recent University of Miami research studies suggest that politicians with deep voices are more likely to win an election than candidates with higher-pitched voices. "With one exception: when running against a female opponent, candidates with higher voices were more popular, especially if they were men," according to Scientific American.
The researchers note that a preference for leaders with deeper voices may be the result of so-called "cavemen instincts." A deep voice is associated with high testosterone, physical strength and aggression. And way back when, those qualities were probably attractive in a leader. High-pitched voices also are thought to convey negative emotions, such as stress and fear.
"Candidate Voice Pitch Influences Election Outcomes" (Political Psychology)