This issue was raised in one of the recent threads on conservatives and Haiti so I thought I'd resuscitate it and make a comment.
I'd like to know more about the study itself. I think it's possible that conservatives might give more to charity than liberals but I suspect the data is skewed. Conservatives tend to be more religious than liberals and I'm betting that a considerable portion of the charitable giving in the study was to churches since they are non-profit institutions. Most of that money goes top pay for minister/priests/bishops/secretaries salaries and building maintenance and upkeep. I would not consider that 'charitable giving' in the same way as a donation to the Red Cross is charitable giving. Many churches in my experience do give a portion of their income to relief, disaster and the needy poor but that is a small percentage of their overall budget compared to something like the Red Cross or Red Crescent.
In addition, many if not all religions have a religious duty to give money to the institution which produces a strong social expectation and sanction that does not exist for non-church members.
In other words, a substantial portion of giving to churches amounts to tax deductible union dues and shouldn't really be factored into the 'charitable giving'. Perhaps it wasn't, but I suspect it was. Anyone have the details on the study?

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13