| Results of SurveyUSA News Poll #10564 |
 | Do you approve or disapprove of the job Charles Grassley is doing as United States Senator? |
| 600 Adults | All | Gender | Age | Race | Party Affiliation | Ideology | Abortion | Gun Ownership | Labor Union | Region | ||||||||||||||||
| Margin of Sampling Error: ± 4% | Male | Female | 18-34 | 35-54 | 55+ | White | Black | Hispanic | Other | Republic | Democrat | Independ | Conserva | Moderate | Liberal | Pro-life | Pro-choi | Yes | No | Yes | No | Northeas | Southeas | Southwes | Northwes | |
| Approve | 60% | 62% | 58% | 48% | 63% | 67% | 61% | ** | ** | ** | 78% | 46% | 65% | 84% | 60% | 41% | 73% | 51% | 64% | 57% | 57% | 61% | 58% | 58% | 54% | 72% |
| Disapprove | 35% | 33% | 38% | 45% | 31% | 30% | 35% | ** | ** | ** | 18% | 50% | 30% | 15% | 35% | 55% | 22% | 45% | 33% | 38% | 39% | 34% | 37% | 38% | 39% | 25% |
| Not Sure | 5% | 5% | 5% | 6% | 6% | 2% | 5% | ** | ** | ** | 4% | 4% | 5% | 1% | 5% | 4% | 5% | 4% | 2% | 5% | 4% | 5% | 5% | 4% | 6% | 4% |
| Total | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% |
| Composition of Adults | 100% | 48% | 52% | 31% | 37% | 32% | 94% | 2% | 2% | 2% | 30% | 41% | 26% | 25% | 44% | 19% | 41% | 55% | 46% | 52% | 20% | 79% | 38% | 20% | 23% | 19% |
 | Do you approve or disapprove of the job Tom Harkin is doing as United States Senator? |
| 600 Adults | All | Gender | Age | Race | Party Affiliation | Ideology | Abortion | Gun Ownership | Labor Union | Region | ||||||||||||||||
| Margin of Sampling Error: ± 4.1% | Male | Female | 18-34 | 35-54 | 55+ | White | Black | Hispanic | Other | Republic | Democrat | Independ | Conserva | Moderate | Liberal | Pro-life | Pro-choi | Yes | No | Yes | No | Northeas | Southeas | Southwes | Northwes | |
| Approve | 51% | 52% | 49% | 48% | 51% | 53% | 51% | ** | ** | ** | 25% | 71% | 51% | 21% | 63% | 61% | 31% | 65% | 48% | 53% | 62% | 47% | 50% | 53% | 50% | 50% |
| Disapprove | 44% | 44% | 44% | 44% | 44% | 43% | 44% | ** | ** | ** | 70% | 23% | 42% | 77% | 30% | 34% | 63% | 29% | 47% | 41% | 34% | 46% | 42% | 43% | 45% | 46% |
| Not Sure | 6% | 5% | 7% | 8% | 5% | 4% | 5% | ** | ** | ** | 5% | 6% | 7% | 2% | 7% | 5% | 6% | 5% | 4% | 6% | 4% | 7% | 7% | 5% | 6% | 4% |
| Total | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% |
| Composition of Adults | 100% | 48% | 52% | 31% | 37% | 32% | 94% | 2% | 2% | 2% | 30% | 41% | 26% | 25% | 44% | 19% | 41% | 55% | 46% | 52% | 20% | 79% | 38% | 20% | 23% | 19% |