[C]onservative women are particularly blissful: about 40 percent say they are very happy. That makes them slightly happier than conservative men and significantly happier than liberal women. The unhappiest of all are liberal men; only about a fifth consider themselves very happy.
About half of happiness is genetically determined. Up to an additional 40 percent comes from the things that have occurred in our recent past — but that won’t last very long.
That leaves just about 12 percent under our control.
Source: Arthur C. Brooks.