| AMERICAN ASSOCIATION FOR JUSTICE POLITICAL ACTION COMMITTEE (AAJ PAC) | $54K | 26 | 1998, 2000, 2002, 2004, 2006, 2008 |
| SEIU COPE (SERVICE EMPLOYEES INTERNATIONAL UNION COMMITTEE ON POLITICAL EDUCATION) | $46K | 16 | 1998, 2000, 2002, 2004, 2006, 2008 |
| NATIONAL ASSOCIATION OF REALTORS POLITICAL ACTION COMMITTEE | $44K | 24 | 1998, 2000, 2002, 2004, 2006, 2008 |
| LABORERS' INTERNATIONAL UNION OF NORTH AMERICA (LIUNA) PAC | $43K | 20 | 1998, 2000, 2002, 2004, 2006, 2008 |
| AMERICAN FEDERATION OF STATE COUNTY & MUNICIPAL EMPLOYEES P E O P L E | $36K | 22 | 1998, 2000, 2002, 2004, 2006, 2008 |
| MACHINISTS NON PARTISAN POLITICAL LEAGUE OF THE INTERNATIONAL ASSOCIATION OF MACHINISTS & AEROSPACE WORKERS | $32K | 11 | 2000, 2002, 2004, 2006, 2008 |
| INTERNATIONAL BROTHERHOOD OF ELECTRICAL WORKERS POLITICAL ACTION COMMITTEE | $31K | 12 | 1998, 2000, 2002, 2004, 2006, 2008 |
| UNITED FOOD AND COMMERCIAL WORKERS INTERNATIONAL UNION ACTIVE BALLOT CLUB | $28K | 17 | 1998, 2000, 2002, 2004, 2006, 2008 |
| ENGINEERS POLITICAL EDUCATION COMMITTEE (EPEC)/INTERNATIONAL UNION OF OPERATING ENGINEERS | $24K | 17 | 1998, 2000, 2002, 2004, 2006, 2008 |
| AMERICA'S CREDIT UNIONS PAC | $22K | 18 | 1998, 2000, 2002, 2004, 2006, 2008 |