In this article, Marc Gerson discusses the potential response of Senators to the June 27, 2013 "Dear Colleague" letter issued by Senate Finance Committee Chairman Max Baucus and Ranking Member Orrin Hatch soliciting views on which tax expenditures should be retained in the Internal Revenue Code as part of a fundamental tax reform effort. "It’s unclear what the level and extent of participation by senators will be," Gerson said. "Some senators are not participating at all. They’re all considering it, but there are a lot of variations."