Are "Conservatives" more charitable?

From Instapundit:

ARE CONSERVATIVES more charitable? "The book's basic findings are that conservatives who practice religion, live in traditional nuclear families and reject the notion that the government should engage in income redistribution are the most generous Americans, by any measure. Conversely, secular liberals who believe fervently in government entitlement programs give far less to charity. They want everyone's tax dollars to support charitable causes and are reluctant to write checks to those causes, even when governments don't provide them with enough money."

Apparently they're not big on paying the taxes to support those entitlement programs, either: "Bono demands more of the taxes he won't pay."