A recent review paper published in the Journal of Social and Political Psychology by Professor Thomas Pettigrew of UC Santa Cruz cites 5 traits Trump supporters have in common.

1 Authoritarianism: A rigid hierarchical view of society.  This trait is triggered by fear of outsiders and by exaggerated threats to gain allegiance.

2 Social Dominance Orientation: (SDO Syndrome). This refers to those who prefer a hierarchy of high status to low status. Those with SDO Syndrome are typically dominant and driven by self-interest.

3 Prejudice: “Dog Whistles” are codes that appeal to those who are subject to bigotry. Bullying and slandering typically incite this syndrome.

4 Lack of Inter-group Contact: A division of zip-codes and isolation of whites are a strong predictor of the lack of true and meaningful interaction with minorities and immigrants.

5 Relative Deprivation: A skewed perception of what one is entitled to whether of economical or social status.