| NRCC | $1.7M | 19 | 2014, 2012 |
| DCCC | $188K | 45 | 2010, 2014, 2006, 2016, 2012, 2018, 2008 |
| IOWA DEMOCRATIC PARTY | $81K | 11 | 2010, 2014, 2012 |
| INTERNATIONAL BROTHERHOOD OF ELECTRICAL WORKERS POLITICAL ACTION COMMITTEE | $73K | 30 | 2010, 2014, 2006, 2020, 2016, 2012, 2018, 2008 |
| AMERICAN FEDERATION OF STATE COUNTY & MUNICIPAL EMPLOYEES P E O P L E | $69K | 32 | 2010, 2014, 2006, 2020, 2016, 2012, 2018, 2008 |
| UAW - V - CAP (UAW VOLUNTARY COMMUNITY ACTION PROGRAM) 'INT'L UNION UNITED AUTOMOBILE AEROSPACE & AGRICULTURAL IMPLEMENT WORKERS OF AMERICA UAW | $66K | 23 | 2010, 2014, 2006, 2020, 2016, 2012, 2018, 2008 |
| CARPENTERS LEGISLATIVE IMPROVEMENT COMMITTEE UNITED BROTHERHOOD OF CARPENTERS AND JOINERS | $65K | 13 | 2010, 2014, 2006, 2016, 2012, 2018, 2008 |
| AMERIPAC: THE FUND FOR A GREATER AMERICA | $65K | 15 | 2010, 2014, 2006, 2020, 2016, 2012, 2018, 2008 |
| UNITED STEELWORKERS POLITICAL ACTION FUND | $65K | 13 | 2010, 2014, 2006, 2016, 2012, 2018, 2008 |
| MACHINISTS NON PARTISAN POLITICAL LEAGUE OF THE INTERNATIONAL ASSOCIATION OF MACHINISTS & AEROSPACE WORKERS | $65K | 13 | 2010, 2014, 2006, 2016, 2012, 2018, 2008 |