Barkley estimated he'd registered to vote "10 to 15" times after canvassers for ACORN, whose political wing has endorsed Barack Obama, relentlessly pursued him and others.
Registering under a fake name is illegal. But officials usually catch multiple registrations and toss them.
The subpoenas come as Republicans have ramped up criticism of ACORN. Officials in Nevada raided ACORN's Las Vegas office Tuesday, accusing the group of signing people up multiple times - in some cases under phony names, like those of Dallas Cowboys.