The Senate Banking Committee is currently hearing testimony on Iran sanctions, with streaming video available here.
Senator Evan Bayh is chairing the hearing.  Bayh is the lead sponsor on the highest-profile piece of sanctions legislation currently being considered by the Senate: S.908, the Iran Refined Petroleum Sanctions Act.  That bill, as explained by its authors, is designed to “cripple” the Iranian economy by sanctioning companies that provide Iran with refined petroleum.
Panelists include former Bush Administration official Nicholas Burns, Dr. Matthew Levitt of the Washington Institute for Near East Policy, Dr. Suzanne Maloney of the Brookings Institution, and Danielle Pletka of the American Enterprise Institute.
Three of the four panelists are strong advocates of draconian sanctions on Iran, with Dr. Maloney placing a greater emphasis on the need for diplomacy and who has only tepid support for broad economic pressures.
The Senate also heard special testimony from Connecticut Senator Joe Lieberman prior to hearing from the other witnesses.