Married people are happier than unmarrieds. People who worship frequently are happier than those who don't. Republicans are happier than Democrats. Rich people are happier than poor people. Whites and Hispanics are happier than blacks. Sunbelt residents are happier than those who live in the rest of the country.via Pew Research via Audaucious Epigone
We also found some interesting non-correlations. People who have children are no happier than those who don't, after controlling for marital status. Retirees are no happier than workers. Pet owners are no happier than those without pets.
One way to find out is by way of a statistical technique known as multiple regression analysis, which gauges the relationship between each factor and happiness while controlling for all the other factors. That analysis shows that the most robust correlations of all those described in this report are health, income, church attendance, being married and, yes, being a Republican.
The same regression analysis also finds that education, gender, and race do not have a statistically significant independent effect on predicting happiness, once all the other factors are controlled.