You can go the IRS website yourself to view the disclosure forms that 527s groups currently have to file. The don't make it real simple. But, if you type in the name of the 527 group, and select both forms 8871 and 8872, you will get some information that includes who started the group, and the contributions they have received (although this is not usually that up to date, as these groups don't have to file very often.)