| MIKULSKI FOR CONGRESS | $275K | 6 | 1986 |
| DEMOCRATIC STATE CENTRAL COMMITTEE OF MARYLAND | $238K | 16 | 2010, 1998, 2004, 1986 |
| DSCC | $181K | 9 | 1992, 1986 |
| AMERICAN FEDERATION OF STATE COUNTY & MUNICIPAL EMPLOYEES P E O P L E | $55K | 25 | 2010, 2002, 2014, 1992, 1988, 1998, 2016, 2004, 1986 |
| INTERNATIONAL ASSOCIATION OF SHEET METAL, AIR, RAIL AND TRANSPORTATION WORKERS POLITICAL ACTION LEAGUE | $50K | 16 | 2010, 1990, 2014, 1992, 1998, 2004, 1986 |
| UAW - V - CAP (UAW VOLUNTARY COMMUNITY ACTION PROGRAM) 'INT'L UNION UNITED AUTOMOBILE AEROSPACE & AGRICULTURAL IMPLEMENT WORKERS OF AMERICA UAW | $50K | 19 | 2010, 1990, 2002, 1992, 1998, 2004, 2008, 1986 |
| AMERICAN ASSOCIATION FOR JUSTICE POLITICAL ACTION COMMITTEE (AAJ PAC) | $47K | 25 | 2010, 2002, 1996, 1994, 2014, 2006, 1992, 1998, 2004, 2008, 1986, 2000 |
| NATIONAL ASSOCIATION OF LETTER CARRIERS OF U.S.A. POLITICAL FUND (LETTER CARRIER POLITICAL FUND) | $47K | 19 | 2010, 1990, 2006, 1992, 1998, 2004, 2008, 1986 |
| NATIONAL ASSOCIATION OF SOCIAL WORKERS INC. POLITICAL ACTION FOR CANDIDATE ELECTION (PACE) | $47K | 25 | 2010, 1990, 2002, 1992, 1998, 2004, 2012, 2008, 1986 |
| AMERICAN NURSES ASSOCIATION PAC | $47K | 37 | 2010, 1990, 2014, 2006, 1992, 1998, 2004, 2012, 2008, 1986 |