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2015 Report Cards
Senate Democrats / Ideology Score

These special year-end statistics dissect the legislative records of Members of Congress during the 2015 legislative year (Jan 6, 2015-Dec 31, 2015), looking at Members who served at the end of that period. This page was last updated on Jan 9, 2016.

A higher or lower number below doesn’t necessarily make a legislator any better or worse, or more or less effective, than other Members of Congress. We present these statistics for you to understand the quantitative aspects of legislating and make your own judgements based on what legislative activities you think are important.

Keep in mind that there are many important aspects of being a legislator besides what can be measured, such as constituent services and performing oversight of the executive branch, which aren’t reflected here.

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Ideology Score

Our unique ideology analysis assigns a score to Members of Congress according to their legislative behavior by how similar the pattern of bills and resolutions they cosponsor are to other Members of Congress. The score can be interpreted as a conservative—liberal scale, although of course it only takes into account a small aspect of reality.

Senate Democrats
most conservative
#1 0.59 Sen. Heidi Heitkamp [D-ND, 2013-2018]
#2 0.57 Sen. Joe Manchin [D-WV]
#3 0.51 Sen. Joe Donnelly [D-IN, 2013-2018]
#4 0.47 Sen. Mark Warner [D-VA]
#5 0.42 Sen. Bill Nelson [D-FL, 2001-2018]
#6 0.42 Sen. Thomas Carper [D-DE]
#7 0.41 Sen. Michael Bennet [D-CO]
#8 0.40 Sen. Jon Tester [D-MT]
#9 0.38 Sen. Claire McCaskill [D-MO, 2007-2018]
#10 0.33 Sen. Tom Udall [D-NM]
#11 0.32 Sen. Timothy “Tim” Kaine [D-VA]
#12 0.28 Sen. Chris Coons [D-DE]
#13 0.28 Sen. Robert “Bob” Casey [D-PA]
#14 0.26 Sen. Ron Wyden [D-OR]
#15 0.25 Sen. Amy Klobuchar [D-MN]
#16 0.25 Sen. Maria Cantwell [D-WA]
#17 0.24 Sen. Harry Reid [D-NV, 1987-2016]
#18 0.24 Sen. Martin Heinrich [D-NM]
#19 0.23 Sen. Benjamin Cardin [D-MD]
#20 0.22 Sen. Jeanne Shaheen [D-NH]
#21 0.22 Sen. Cory Booker [D-NJ]
#22 0.19 Sen. Gary Peters [D-MI]
#23 0.19 Sen. Patrick Leahy [D-VT]
#24 0.19 Sen. Robert “Bob” Menendez [D-NJ]
#25 0.16 Sen. Christopher Murphy [D-CT]
#26 0.16 Sen. Brian Schatz [D-HI]
#27 0.15 Sen. Debbie Stabenow [D-MI]
#28 0.14 Sen. Dianne Feinstein [D-CA]
#29 0.14 Sen. Barbara Mikulski [D-MD, 1987-2016]
#30 0.12 Sen. Charles “Chuck” Schumer [D-NY]
#31 0.12 Sen. Sherrod Brown [D-OH]
#32 0.11 Sen. Mazie Hirono [D-HI]
#33 0.11 Sen. Patty Murray [D-WA]
#34 0.09 Sen. Jeff Merkley [D-OR]
#35 0.08 Sen. Kirsten Gillibrand [D-NY]
#36 0.08 Sen. Richard Blumenthal [D-CT]
#37 0.07 Sen. John “Jack” Reed [D-RI]
#38 0.07 Sen. Barbara Boxer [D-CA, 1993-2016]
#39 0.07 Sen. Tammy Baldwin [D-WI]
#40 0.07 Sen. Richard Durbin [D-IL]
#41 0.07 Sen. Sheldon Whitehouse [D-RI]
#42 0.05 Sen. Alan “Al” Franken [D-MN, 2009-2017]
#43 0.03 Sen. Edward “Ed” Markey [D-MA]
#44 0.00 Sen. Elizabeth Warren [D-MA]
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For more, see our methodology. An ideology score is not computed for Members of Congress who introduced fewer than 10 bills or who have a low leadership score, as there is usually not enough data in these cases to compute reliable statistics. Note that because on this page only legislative activity in 2015 is considered, the ideology score here may differ from those elsewhere on GovTrack.

Additional Notes

The Speaker’s Votes: Missed votes are not computed for the Speaker of the House. According to current House rules, the Speaker of the House is not required to vote in “ordinary legislative proceedings.” In practice this means the Speaker of the House rarely votes but is not considered absent.

Leadership/Ideology: The leadership and ideology scores are not displayed for Members of Congress who introduced fewer than 10 bills, or, for ideology, for Members of Congress that have a low leadership score, as there is usually not enough data in these cases to compute reliable leadership and ideology statistics.

Missing Bills: We exclude bills from some statistics where the sponsor’s original intent is not in the final bill because the bill’s text was replaced in whole with unrelated provisions (i.e. it became a vehicle for passage of unrelated provisions).

Ranking Members (RkMembs): The chair of a committee is always selected from the political party that holds the most seats in the chamber, called the “majority party”. The “ranking member” (sometimes “RkMembs”) is the title given to the senior-most member of the committee not in the majority party.

Freshmen/Sophomores: Freshmen and sophomores are Members of Congress whose first term (in the same chamber at the end of 2015) was the 114th Congress (freshmen) or 113th (sophomores). Members of Congress who took office within the last few months of a Congress are considered freshmen in the next Congress as well.