The Senate:

59 Democrats, 41 Republicans, and an average obstruction rate of 31.4%.

The Whole List

Name Obstruction Rate
Jim DeMint (R-SC) 93.8%
Tom Coburn (R-OK) 89.4%
Jim Bunning (R-KY) 89.3%
Jim Inhofe (R-OK) 86.9%
Jeff Sessions (R-AL) 86.9%
John Ensign (R-NV) 84.1%
Sam Brownback (R-KS) 83.5%
John Cornyn (R-TX) 82.3%
Jon Kyl (R-AZ) 81.4%
John McCain (R-AZ) 81.2%
Pat Roberts (R-KS) 81.0%
Jim Risch (R-ID) 80.5%
Mike Crapo (R-ID) 80.2%
Richard Shelby (R-AL) 79.5%
David Vitter (R-LA) 79.2%
Mike Enzi (R-WY) 79.1%
John Barrasso (R-WY) 78.4%
Mitch McConnell (R-KY) 78.2%
Richard Burr (R-NC) 77.8%
Johnny Isakson (R-GA) 77.4%
Kay Hutchison (R-TX) 76.1%
John Thune (R-SD) 75.9%
Bob Corker (R-TN) 75.6%
C. Saxby Chambliss (R-GA) 75.3%
Chuck Grassley (R-IA) 75.0%
Roger Wicker (R-MS) 73.6%
Lindsey Graham (R-SC) 73.5%
George LeMieux (R-FL) 73.4%
Mike Johanns (R-NE) 73.3%
Orrin Hatch (R-UT) 69.5%
Lamar Alexander (R-TN) 68.6%
Judd Gregg (R-NH) 68.1%
Bob Bennett (R-UT) 67.9%
Kit Bond (R-MO) 65.4%
Thad Cochran (R-MS) 64.0%
Scott Brown (R-MA) 63.8%
Richard Lugar (R-IN) 57.0%
George Voinovich (R-OH) 52.4%
Lisa Murkowski (R-AK) 51.9%
Susan Collins (R-ME) 38.2%
Olympia Snowe (R-ME) 38.2%
Russell Feingold (D-WI) 19.3%
Ben Nelson (D-NE) 18.2%
Harry Reid (D-NV) 13.5%
Joseph Lieberman (I-CT) 9.4%
Kay Hagan (D-NC) 9.1%
Carte Goodwin (D-WV) 7.1%
Claire McCaskill (D-MO) 5.8%
Mark Warner (D-VA) 5.8%
Mark Begich (D-AK) 4.8%
Arlen Specter (D-PA) 4.7%
Blanche Lincoln (D-AR) 4.7%
Mark Pryor (D-AR) 4.7%
Jon Tester (D-MT) 4.7%
Evan Bayh (D-IN) 4.6%
Maria Cantwell (D-WA) 4.5%
Mark Udall (D-CO) 4.5%
Jim Webb (D-VA) 4.5%
Max Baucus (D-MT) 4.5%
Mary Landrieu (D-LA) 3.5%
Bernie Sanders (I-VT) 3.4%
Jay Rockefeller (D-WV) 2.5%
Sherrod Brown (D-OH) 2.4%
Ron Wyden (D-OR) 2.4%
Kirsten Gillibrand (D-NY) 2.4%
Tom Harkin (D-IA) 2.4%
Patrick Leahy (D-VT) 2.4%
Michael Bennet (D-CO) 2.3%
Kent Conrad (D-ND) 2.3%
Frank Lautenberg (D-NJ) 2.3%
Jeff Merkley (D-OR) 2.3%
Bill Nelson (D-FL) 2.3%
Byron Dorgan (D-ND) 2.3%
Dick Durbin (D-IL) 2.3%
Herb Kohl (D-WI) 2.3%
Jeff Bingaman (D-NM) 2.2%
Tom Carper (D-DE) 2.2%
Carl Levin (D-MI) 2.2%
Al Franken (D-MN) 1.4%
Ted Kaufman (D-DE) 1.4%
Roland Burris (D-IL) 1.3%
Daniel Inouye (D-HI) 1.2%
Robert Menendez (D-NJ) 1.2%
Debbie Stabenow (D-MI) 1.2%
Barbara Boxer (D-CA) 1.1%
John Kerry (D-MA) 1.1%
Barbara Mikulski (D-MD) 1.1%
Bob Casey (D-PA) 1.1%
Tim Johnson (D-SD) 1.1%
Patty Murray (D-WA) 1.1%
Jack Reed (D-RI) 1.1%
Sheldon Whitehouse (D-RI) 1.1%
Daniel Akaka (D-HI) 1.1%
Ben Cardin (D-MD) 1.1%
Chris Dodd (D-CT) 1.1%
Dianne Feinstein (D-CA) 1.1%
Amy Klobuchar (D-MN) 1.1%
Chuck Schumer (D-NY) 1.1%
Jeanne Shaheen (D-NH) 1.1%
Tom Udall (D-NM) 1.1%

Least Obstructionist Republicans

Members of the minority party that have voted for cloture most often.

Susan Collins (R-ME) 38.2%
Olympia Snowe (R-ME) 38.2%
Lisa Murkowski (R-AK) 51.9%
George Voinovich (R-OH) 52.4%
Richard Lugar (R-IN) 57.0%

Most Obstructionist Democrats

Members of the majority party that have voted against cloture most often.

Russell Feingold (D-WI) 19.3%
Ben Nelson (D-NE) 18.2%
Harry Reid (D-NV) 13.5%
Kay Hagan (D-NC) 9.1%
Carte Goodwin (D-WV) 7.1%

Most Vulnerable in 2010

Incumbents that face difficult re-election campaigns, based on FiveThirtyEight's rankings.

Republicans

Jim Bunning (R-KY) 89.3%
Richard Burr (R-NC) 77.8%
David Vitter (R-LA) 79.2%
Chuck Grassley (R-IA) 75.0%
Tom Coburn (R-OK) 89.4%

Democrats

Chris Dodd (D-CT) 1.1%
Michael Bennet (D-CO) 2.3%
Roland Burris (D-IL) 1.3%
Harry Reid (D-NV) 13.5%
Arlen Specter (D-PA) 4.7%