| — | cosponsor_of_bill | SRES 364 — A resolution expressing the sense of the Senate concerning oil markets. | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 1141 — Biodiesel Energy Development Act of 1997 | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 1544 — National Trails System Improvements Act of 1988 | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 1643 — Effigy Mounds National Monument Additions Act | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 1646 — Propane Education and Research Act of 1996 | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 1725 — National Discovery Trails Act of 1996 | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 1891 — Roadless Area Conservation Act of 2011 | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 1969 — Alexander Hamilton Boyhood Home Study Act of 2007 | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 2042 — An Act to authorize the Vietnam Women's Memorial Project, Inc., to construct within the Vie | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 2068 — Lewis and Clark Rural Water System Act of 1994 | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 2080 — A bill to designate a site for the relocation of the public facility of the National Museum | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 21 — California Desert Protection Act of 1994 | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 2197 — PACE-Energy Act | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 2199 — American Heritage Trust Act of 1988 | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 2346 — National Discovery Trails Act of 2014 | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 2364 — Roadless Area Conservation Act of 2006 | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 247 — State Energy Efficiency Programs Improvement Act of 1990 | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 257 — Mineral Exploration and Development Act of 1993 | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 2790 — Roadless Area Conservation Act of 2002 | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 2794 — Department of Energy Contractor Employee Equitable Treatment Act of 2006 | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 2901 — 10 Million Solar Roofs Act of 2014 | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 311 — A bill to authorize the Disabled Veterans' LIFE Memorial Foundation to establish a memorial | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 3385 — Authorized Rural Water Projects Completion Act | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 3460 — 10 Million Solar Roofs Act of 2010 | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 356 — EPACT Alternative Fuel Flexibility Act of 2003 | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 3923 — Let the States Innovate on Sustainable Energy Act of 2010 | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 398 — Implementation of National Consensus Appliance Agreements Act of 2011 | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 4020 — Renewable Fuels Promotion Act | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 470 — A bill to extend the authority for the construction of a memorial to Martin Luther King, Jr. | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 488 — Renewable Energy and Energy Efficiency Technology Competitiveness Act of 1989 | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 715 — Authorized Rural Water Projects Completion Act | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 734 — A bill to permanently prohibit the Secretary of the Interior from preparing for or conductin | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 736 — A bill to amend the Outer Continental Shelf Lands Act. | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 979 — America's Red Rock Wilderness Act of 2011 | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | SCONRES 88 — A concurrent resolution expressing the sense of Congress concerning drawdowns of the St | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | S 1069 — National Discovery Trails Act of 1998 | — | cosponsor | sponsorship |
| — | cosponsor_of_bill | SRES 420 — A resolution recommending expenditures for an appropriate visitors center at Little Rock | — | cosponsor | sponsorship |
| — | independent_committee_of | FRIENDS OF MEDICAL RESEARCH | — | | candidate_committees |
| — | joint_fundraising_committee_of | IOWA SENATE 2002 | — | | candidate_committees |
| — | joint_fundraising_committee_of | DORGAN VICTORY FUND | — | | candidate_committees |
| — | joint_fundraising_committee_of | CORZINE 2002 VICTORY FUND | — | | candidate_committees |
| — | joint_fundraising_committee_of | IOWA SENATE 2008 | — | | candidate_committees |
| — | joint_fundraising_committee_of | IOWA-LOUISIANA VICTORY FUND | — | | candidate_committees |
| — | joint_fundraising_committee_of | SENATE VICTORY FUND | — | | candidate_committees |
| — | principal_candidate_of | CITIZENS FOR HARKIN | — | | candidate_committees |
| 2011-01-25 | sponsor_of_bill | S 187 — Biofuels Market Expansion Act of 2011 | — | sponsor | sponsorship |
| 2006-09-29 | sponsor_of_bill | S 4003 — Ethanol Infrastructure Expansion Act of 2006 | — | sponsor | sponsorship |
| 1991-06-11 | sponsor_of_bill | S 1269 — Renewable Hydrogen Energy Research and Development Act of 1991 | — | sponsor | sponsorship |