I actually laughed when I came across this research article in this week's Science, titled "Conservatives report, but liberals display, greater happiness."
Previous studies had shown that conservatives were happier than liberals, apparently termed the "ideological happiness gap." However, those studies relied on self-reporting, which makes it dubious whether the association is true. One could say that conservatives are better at lying to themselves, while liberals just enjoy being debbie downers.
The researchers decided to go beyond self-reporting by analyzing the photos and writings of politicians, Twitter users, LinkedIn users, and online survey takers. The researchers found that those that identified with liberal ideals tended to genuinely smile more, and use happier language.
Now, I don't know if that actually means liberals are happier, but they're at least putting on a more convincing act of being happy. At the very least, it debunks the belief that conservatives are more content with their lives than liberals.
What I would love to know is how the U.S. politicians fared in happy indicators compared to the rest of us. Cause being in politics seems like a great way to be miserable...