Generous to a fault, with other people's money

Arthur Brooks, the author of a book on donors to charity, “Who Really Cares,” cites data that households headed by conservatives give 30 percent more to charity than households headed by liberals. A study by Google found an even greater disproportion: average annual contributions reported by conservatives were almost double those of liberals.

[...]

“When I started doing research on charity,” Mr. Brooks wrote, “I expected to find that political liberals — who, I believed, genuinely cared more about others than conservatives did — would turn out to be the most privately charitable people. So when my early findings led me to the opposite conclusion, I assumed I had made some sort of technical error. I re-ran analyses. I got new data. Nothing worked. In the end, I had no option but to change my views.”

Bleeding Heart Tightwads, Nicholas Kristof, New York Times - 21 Dec 2008

Huh.

This makes a lot more sense, a little further into the column, when the following information is disclosed:

• The percentage of philanthropy among regular churchgoers is about the same across both liberal and conservative groups, and significantly higher than average.
• And donations to one's own church were counted as private charity.

The determining factor here is membership in a community of faith and financial support of same, not "conservative" or "liberal" beliefs per se. That there are more belonging/donating believers among conservatives than liberals is not a terribly surprising thing.