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2015 Senate Scores
Overview

The Lugar Center - McCourt School Bipartisan Index
Senate Scores
114th Congress First Session (2015)
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| Senator (by score) | Senator (alphabetical) | |||||||||||
| # | Name | State | Party | Score | # | Name | State | Party | Score | |||
| 1 | Collins | Susan | ME | R | 2.27114 | 47 | Alexander | Lamar | TN | R | -0.17613 | |
| 2 | Donnelly | Joe | IN | D | 1.83206 | 11 | Ayotte | Kelly | NH | R | 0.78900 | |
| 3 | Kirk | Mark | IL | R | 1.49994 | 80 | Baldwin | Tammy | WI | D | -0.87054 | |
| 4 | Manchin | Joe | WV | D | 1.24699 | 66 | Barrasso | John | WY | R | -0.64640 | |
| 5 | Grassley | Chuck | IA | R | 1.21807 | 23 | Bennet | Michael | CO | D | 0.38591 | |
| 6 | Portman | Rob | OH | R | 1.10254 | 82 | Blumenthal | Richard | CT | D | -0.92150 | |
| 7 | Blunt | Roy | MO | R | 0.92726 | 7 | Blunt | Roy | MO | R | 0.92726 | |
| 8 | Moran | Jerry | KS | R | 0.90693 | 61 | Booker | Cory | NJ | D | -0.52868 | |
| 9 | Heller | Dean | NV | R | 0.89984 | 25 | Boozman | John | AR | R | 0.30580 | |
| 10 | Coons | Chris | DE | D | 0.87911 | 96 | Boxer | Barbara | CA | D | -1.38343 | |
| 11 | Ayotte | Kelly | NH | R | 0.78900 | 74 | Brown | Sherrod | OH | D | -0.75974 | |
| 12 | Wicker | Roger | MS | R | 0.74979 | 29 | Burr | Richard | NC | R | 0.23059 | |
| 13 | Graham | Lindsey | SC | R | 0.72487 | 41 | Cantwell | Maria | WA | D | -0.08598 | |
| 14 | Capito | Shelley | WV | R | 0.71897 | 14 | Capito | Shelley | WV | R | 0.71897 | |
| 15 | Warner | Mark | VA | D | 0.69749 | 32 | Cardin | Ben | MD | D | 0.17540 | |
| 16 | Toomey | Pat | PA | R | 0.69237 | 22 | Carper | Tom | DE | D | 0.39953 | |
| 17 | Hoeven | John | ND | R | 0.67384 | 43 | Casey | Bob | PA | D | -0.11249 | |
| 18 | Corker | Bob | TN | R | 0.63726 | 68 | Cassidy | Bill | LA | R | -0.65204 | |
| 19 | Heitkamp | Heidi | ND | D | 0.59594 | 75 | Coats | Dan | IN | R | -0.81543 | |
| 20 | Klobuchar | Amy | MN | D | 0.48111 | 40 | Cochran | Thad | MS | R | -0.05974 | |
| 21 | McCaskill | Claire | MO | D | 0.46508 | 1 | Collins | Susan | ME | R | 2.27114 | |
| 22 | Carper | Tom | DE | D | 0.39953 | 10 | Coons | Chris | DE | D | 0.87911 | |
| 23 | Bennet | Michael | CO | D | 0.38591 | 18 | Corker | Bob | TN | R | 0.63726 | |
| 24 | Peters | Gary | MI | D | 0.33644 | 57 | Cornyn | John | TX | R | -0.41139 | |
| 25 | Boozman | John | AR | R | 0.30580 | 88 | Cotton | Tom | AR | R | -1.13847 | |
| 26 | Tester | Jon | MT | D | 0.30387 | 45 | Crapo | Mike | ID | R | -0.13692 | |
| 27 | Gardner | Cory | CO | R | 0.25083 | 97 | Cruz | Ted | TX | R | -1.40999 | |
| 28 | Rubio | Marco | FL | R | 0.24861 | 55 | Daines | Steve | MT | R | -0.40341 | |
| 29 | Burr | Richard | NC | R | 0.23059 | 2 | Donnelly | Joe | IN | D | 1.83206 | |
| 30 | King | Angus | ME | D | 0.22004 | 92 | Durbin | Dick | IL | D | -1.29778 | |
| 31 | Nelson | Bill | FL | D | 0.17624 | 34 | Enzi | Mike | WY | R | 0.14226 | |
| 32 | Cardin | Ben | MD | D | 0.17540 | 38 | Ernst | Joni | IA | R | 0.03688 | |
| 33 | Sessions | Jeff | AL | R | 0.16831 | 62 | Feinstein | Dianne | CA | D | -0.53303 | |
| 34 | Enzi | Mike | WY | R | 0.14226 | 72 | Fischer | Deb | NE | R | -0.74208 | |
| 35 | Murkowski | Lisa | AK | R | 0.12918 | 48 | Flake | Jeff | AZ | R | -0.18002 | |
| 36 | Isakson | Johnny | GA | R | 0.11754 | 76 | Franken | Al | MN | D | -0.82968 | |
| 37 | Tillis | Thom | NC | R | 0.08615 | 27 | Gardner | Cory | CO | R | 0.25083 | |
| 38 | Ernst | Joni | IA | R | 0.03688 | 67 | Gillibrand | Kirsten | NY | D | -0.64651 | |
| 39 | Shaheen | Jeanne | NH | D | -0.00243 | 13 | Graham | Lindsey | SC | R | 0.72487 | |
| 40 | Cochran | Thad | MS | R | -0.05974 | 5 | Grassley | Chuck | IA | R | 1.21807 | |
| 41 | Cantwell | Maria | WA | D | -0.08598 | 58 | Hatch | Orrin | UT | R | -0.41531 | |
| 42 | Thune | John | SD | R | -0.09615 | 73 | Heinrich | Martin | NM | D | -0.74907 | |
| 43 | Casey | Bob | PA | D | -0.11249 | 19 | Heitkamp | Heidi | ND | D | 0.59594 | |
| 44 | Sullivan | Dan | AK | R | -0.12527 | 9 | Heller | Dean | NV | R | 0.89984 | |
| 45 | Crapo | Mike | ID | R | -0.13692 | 87 | Hirono | Mazie | HI | D | -1.03404 | |
| 46 | Kaine | Tim | VA | D | -0.15601 | 17 | Hoeven | John | ND | R | 0.67384 | |
| 47 | Alexander | Lamar | TN | R | -0.17613 | 65 | Inhofe | Jim | OK | R | -0.60721 | |
| 48 | Flake | Jeff | AZ | R | -0.18002 | 36 | Isakson | Johnny | GA | R | 0.11754 | |
| 49 | Stabenow | Debbie | MI | D | -0.22108 | 52 | Johnson | Ron | WI | R | -0.28570 | |
| 50 | Roberts | Pat | KS | R | -0.26357 | 46 | Kaine | Tim | VA | D | -0.15601 | |
| 51 | Paul | Rand | KY | R | -0.26934 | 30 | King | Angus | ME | D | 0.22004 | |
| 52 | Johnson | Ron | WI | R | -0.28570 | 3 | Kirk | Mark | IL | R | 1.49994 | |
| 53 | Leahy | Patrick | VT | D | -0.32387 | 20 | Klobuchar | Amy | MN | D | 0.48111 | |
| 54 | Scott | Tim | SC | R | -0.34351 | 69 | Lankford | James | OK | R | -0.65338 | |
| 55 | Daines | Steve | MT | R | -0.40341 | 53 | Leahy | Patrick | VT | D | -0.32387 | |
| 56 | Udall | Tom | NM | D | -0.40414 | 71 | Lee | Mike | UT | R | -0.73718 | |
| 57 | Cornyn | John | TX | R | -0.41139 | 4 | Manchin | Joe | WV | D | 1.24699 | |
| 58 | Hatch | Orrin | UT | R | -0.41531 | 91 | Markey | Ed | MA | D | -1.27685 | |
| 59 | McCain | John | AZ | R | -0.51318 | 59 | McCain | John | AZ | R | -0.51318 | |
| 60 | Risch | Jim | ID | R | -0.52800 | 21 | McCaskill | Claire | MO | D | 0.46508 | |
| 61 | Booker | Cory | NJ | D | -0.52868 | 84 | Menéndez | Bob | NJ | D | -0.93944 | |
| 62 | Feinstein | Dianne | CA | D | -0.53303 | 95 | Merkley | Jeff | OR | D | -1.33805 | |
| 63 | Wyden | Ron | OR | D | -0.53909 | 81 | Mikulski | Barbara | MD | D | -0.87178 | |
| 64 | Vitter | David | LA | R | -0.55020 | 8 | Moran | Jerry | KS | R | 0.90693 | |
| 65 | Inhofe | Jim | OK | R | -0.60721 | 35 | Murkowski | Lisa | AK | R | 0.12918 | |
| 66 | Barrasso | John | WY | R | -0.64640 | 83 | Murphy | Chris | CT | D | -0.93717 | |
| 67 | Gillibrand | Kirsten | NY | D | -0.64651 | 86 | Murray | Patty | WA | D | -0.99833 | |
| 68 | Cassidy | Bill | LA | R | -0.65204 | 31 | Nelson | Bill | FL | D | 0.17624 | |
| 69 | Lankford | James | OK | R | -0.65338 | 51 | Paul | Rand | KY | R | -0.26934 | |
| 70 | Schumer | Chuck | NY | D | -0.72719 | 90 | Perdue | David | GA | R | -1.18492 | |
| 71 | Lee | Mike | UT | R | -0.73718 | 24 | Peters | Gary | MI | D | 0.33644 | |
| 72 | Fischer | Deb | NE | R | -0.74208 | 6 | Portman | Rob | OH | R | 1.10254 | |
| 73 | Heinrich | Martin | NM | D | -0.74907 | 78 | Reed | Jack | RI | D | -0.84384 | |
| 74 | Brown | Sherrod | OH | D | -0.75974 | 60 | Risch | Jim | ID | R | -0.52800 | |
| 75 | Coats | Dan | IN | R | -0.81543 | 50 | Roberts | Pat | KS | R | -0.26357 | |
| 76 | Franken | Al | MN | D | -0.82968 | 77 | Rounds | Mike | SD | R | -0.82972 | |
| 77 | Rounds | Mike | SD | R | -0.82972 | 28 | Rubio | Marco | FL | R | 0.24861 | |
| 78 | Reed | Jack | RI | D | -0.84384 | 98 | Sanders | Bernie | VT | D | -1.95559 | |
| 79 | Schatz | Brian | HI | D | -0.84394 | 89 | Sasse | Ben | NE | R | -1.15644 | |
| 80 | Baldwin | Tammy | WI | D | -0.87054 | 79 | Schatz | Brian | HI | D | -0.84394 | |
| 81 | Mikulski | Barbara | MD | D | -0.87178 | 70 | Schumer | Chuck | NY | D | -0.72719 | |
| 82 | Blumenthal | Richard | CT | D | -0.92150 | 54 | Scott | Tim | SC | R | -0.34351 | |
| 83 | Murphy | Chris | CT | D | -0.93717 | 33 | Sessions | Jeff | AL | R | 0.16831 | |
| 84 | Menéndez | Bob | NJ | D | -0.93944 | 39 | Shaheen | Jeanne | NH | D | -0.00243 | |
| 85 | Warren | Elizabeth | MA | D | -0.94121 | 94 | Shelby | Richard | AL | R | -1.31178 | |
| 86 | Murray | Patty | WA | D | -0.99833 | 49 | Stabenow | Debbie | MI | D | -0.22108 | |
| 87 | Hirono | Mazie | HI | D | -1.03404 | 44 | Sullivan | Dan | AK | R | -0.12527 | |
| 88 | Cotton | Tom | AR | R | -1.13847 | 26 | Tester | Jon | MT | D | 0.30387 | |
| 89 | Sasse | Ben | NE | R | -1.15644 | 42 | Thune | John | SD | R | -0.09615 | |
| 90 | Perdue | David | GA | R | -1.18492 | 37 | Tillis | Thom | NC | R | 0.08615 | |
| 91 | Markey | Ed | MA | D | -1.27685 | 16 | Toomey | Pat | PA | R | 0.69237 | |
| 92 | Durbin | Dick | IL | D | -1.29778 | 56 | Udall | Tom | NM | D | -0.40414 | |
| 93 | Whitehouse | Sheldon | RI | D | -1.29820 | 64 | Vitter | David | LA | R | -0.55020 | |
| 94 | Shelby | Richard | AL | R | -1.31178 | 15 | Warner | Mark | VA | D | 0.69749 | |
| 95 | Merkley | Jeff | OR | D | -1.33805 | 85 | Warren | Elizabeth | MA | D | -0.94121 | |
| 96 | Boxer | Barbara | CA | D | -1.38343 | 93 | Whitehouse | Sheldon | RI | D | -1.29820 | |
| 97 | Cruz | Ted | TX | R | -1.40999 | 12 | Wicker | Roger | MS | R | 0.74979 | |
| 98 | Sanders | Bernie | VT | D | -1.95559 | 63 | Wyden | Ron | OR | D | -0.53909 | |
| GovTrack data was used in the production of these scores | ||||||||||||
| Notes: | ||||||||||||
| Majority Leader Mitch McConnell (R-KY) and Minority Leader Harry Reid (D-NV) are excluded. | ||||||||||||
| Senators who are independent but caucus with a party for purposes of determining which party is in the majority are counted as a member of that party. | ||||||||||||
