| DCCC | $21K | 9 | 2006, 1988, 2004 |
| MACHINISTS NON PARTISAN POLITICAL LEAGUE OF THE INTERNATIONAL ASSOCIATION OF MACHINISTS & AEROSPACE WORKERS | $20K | 5 | 1988, 2004, 1982 |
| UNITED FOOD AND COMMERCIAL WORKERS INTERNATIONAL UNION ACTIVE BALLOT CLUB | $12K | 11 | 1988, 2004, 1982 |
| AFL-CIO COPE POLITICAL CONTRIBUTIONS COMMITTEE | $12K | 8 | 1988, 2004, 1982 |
| UAW - V - CAP (UAW VOLUNTARY COMMUNITY ACTION PROGRAM) 'INT'L UNION UNITED AUTOMOBILE AEROSPACE & AGRICULTURAL IMPLEMENT WORKERS OF AMERICA UAW | $11K | 4 | 1988, 2004 |
| IOWA DEMOCRATIC PARTY | $10K | 3 | 1982 |
| AMERICAN FEDERATION OF STATE COUNTY & MUNICIPAL EMPLOYEES P E O P L E | $10K | 14 | 1984, 1988, 2004, 1982 |
| INTERNATIONAL BROTHERHOOD OF ELECTRICAL WORKERS POLITICAL ACTION COMMITTEE | $9K | 8 | 2006, 1988, 2004, 1982 |
| FIRST DISTRICT DEMOCRATIC CENTRAL COMMITTEE | $8K | 14 | 1984, 1988, 1982 |
| INT'L ASSOCIATION OF BRIDGE, STRUCTURAL, ORNAMENTAL AND REINFORCING IRON WORKERS (IPAL) | $8K | 4 | 2006, 1988, 1982 |