The following table measures the percent of time, since January 2011, that each senator has voted with his or her party when a majority of the party voted one way and the majority of the opposing party voted the other way. This percentage, known as a “party unity vote,” is intended to measure how often a senator is willing to cross the aisle when the parties are at odds.
| Collins | 45% |
| Scott Brown | 47% |
| Snowe | 53% |
| Murkowski | 66% |
| Cochran | 72% |
| Hoeven | 72% |
| Manchin | 73% |
| Ben Nelson | 75% |
| McCaskill | 77% |
| Blunt | 79% |
| Kirk | 81% |
| Lugar | 81% |
| Heller | 83% |
| Johanns | 83% |
| Pryor | 84% |
| Webb | 84% |
| Lieberman | 84% |
| Alexander | 85% |
| Hutchison | 85% |
| Wicker | 85% |
| Moran | 86% |
| Roberts | 86% |
| Graham | 87% |
| Grassley | 87% |
| Hagan | 88% |
| Landrieu | 88% |
| Tester | 88% |
| Warner | 88% |
| Boozman | 88% |
| Portman | 88% |
| Begich | 90% |
| Benet | 90% |
| Carper | 90% |
| Bill Nelson | 90% |
| Mark Udall | 90% |
| Shelby | 90% |
| Thune | 90% |
| Baucus | 91% |
| Casey | 91% |
| Stabenow | 91% |
| Coats | 91% |
| Isakson | 91% |
| Vitter | 91% |
| Conrad | 92% |
| Klobuchar | 92% |
| Kohl | 92% |
| Corker | 92% |
| Paul | 92% |
| Rubio | 92% |
| Cantwell | 93% |
| Reid | 93% |
| Ayotte | 93% |
| Chambliss | 93% |
| Lee | 93% |
| Sessions | 93% |
| Coons | 94% |
| Shaheen | 94% |
| Barrasso | 94% |
| Burr | 94% |
| DeMint | 94% |
| Enzi | 94% |
| Inhofe | 94% |
| Inouye | 95% |
| Kerry | 95% |
| Levin | 95% |
| Menendez | 95% |
| Sanders | 95% |
| Coburn | 95% |
| Crapo | 95% |
| Kyl | 95% |
| McCain | 95% |
| McConnell | 95% |
| Risch | 95% |
| Toomey | 95% |
| Akaka | 96% |
| Blumenthal | 96% |
| Feinstein | 96% |
| Johnson | 96% |
| Merkley | 96% |
| Murray | 96% |
| Reed | 96% |
| Wyden | 96% |
| Hatch | 96% |
| Bingaman | 97% |
| Sherrod Brown | 97% |
| Durbin | 97% |
| Gillibrand | 97% |
| Harkin | 97% |
| Lautenberg | 97% |
| Leahy | 97% |
| Mikulski | 97% |
| Schumer | 97% |
| Whitehouse | 97% |
| Cornyn | 97% |
| Boxer | 98% |
| Franken | 98% |
| Rockefeller | 98% |
| Ron Johnson | 98% |
| Cardin | 99% |
| Tom Udall | 100% |