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Vermont Sen. Bernie Sanders has made more left-leaning topics part of the national political conversation this year during his presidential run. He asks, “Do we continue the 40-year decline of our middle class and the growing gap between the very rich and everyone else, or do we fight for a progressive economic agenda that creates jobs, raises wages, protects the environment and provides health care for all?” The question Sanders poses on his campaign website highlights key elements of modern liberalism, from income inequality to health care reform to equal rights.

Although the media might suggest an “era of liberal dominance,” the movement lacks a majority in Congress. The GOP leadership in both the House and Senate means Republicans can kill bills and resolutions championed by Democrats, who react to this deadlock by pushing liberal policies that have “no chance of passage.” Although their efforts in Congress are largely fruitless in the current power dynamic, notable die-hard liberals remain active in their legislative roles.

InsideGov wanted to learn more about these hard-core Democrats, and turned to GovTrack’s Ideology Score to determine the most liberal members of Congress. The score assigns numerical values to members of Congress based on the progressive nature of their bills during the first session of the 114th Congress. Only members that introduced more than 10 bills during this session were included in the ideology calculation. Those closest to the value of 0 are the most liberal, with scores nearing 1 representing the most conservative. We count down the list of the 29 most liberal members of Congress and explore some of their proposed pieces of legislation.

Note: For the sake of simplicity, we round the “Ideology Score” to two significant figures, which results in ties. Govtrack calculates the score to nine significant figures. The majority of these ties do not exist in the unrounded list. If a true tie occurs, it is noted on the slide. If a member of Congress introduced fewer than 10 bills, they are not included in the calculation due to insufficient data.

#29. Rep. Chris Van Hollen

Ideology Score: 0.14

Rep. Chris Van Hollen Jr. from Maryland introduced the progressive-leaning Healthy Climate and Family Security Act of 2015, which attempted to cap the emission of greenhouse gases through a system of carbon permits. It has been assigned to congressional committee since February 2015.

#28. Sen. Barbara A. Mikulski

Ideology Score: 0.14

Maryland Sen. Barbara Mikulski sponsored the PALS Act, which aimed to ensure access to screening mammography services.

#27. Rep. Mark Takano

Ideology Score: 0.13

Rep. Mark Takano, from California’s 41st congressional district, introduced the Social Security and Medicare Parity Act of 2015, which aimed to amend the Social Security Act to include equal treatment for those in same-sex marriages

#26. Rep. John Conyers Jr.

Ideology Score: 0.13

Michigan Rep. John Conyers Jr. introduced the End Racial Profiling Act of 2015, which intended to end racial profiling by law enforcement agencies through new laws and programs. “The killing of Walter Scott – arising from a traffic stop – along with the deaths of Freddie Gray, Michael Brown, Eric Garner, and Sean Bell, Tamir Rice, Oscar Grant and many more highlight the fact that racial profiling remains a divisive issue in communities across our nation,” Conyers said in a press release about the proposed legislation.

#25. Sen. Charles E. Schumer

Ideology Score: 0.12

New York Sen. Charles “Chuck” Schumer introduced the Human Rights for Girls Act, which prohibits the use of certain restraints on pregnant juveniles. When he announced the bill in July 2015, Schumer said: “Just because a woman is behind bars, doesn’t mean she shouldn’t have access to basic human rights.”

#24. Rep. Yvette D. Clarke

Ideology Score: 0.12

Rep. Yvette Clarke, from New York’s 9th District, introduced Aidan’s Law, which aimed to require newborn screening for adrenoleukodystrophy, a potentially deadly genetic disorder.

#23. Sen. Sherrod Brown

Ideology Score: 0.12

Ohio Sen. Sherrod Brown sponsored the Strong Lungs, Strong Lives Act of 2015, which planned to encourage the use of services to help people stop smoking. It has remained in a congressional committee since May 2015.

#22. Sen. Mazie K. Hirono

Ideology Score: 0.11

Sen. Mazie Hirono, the junior senator from Hawaii, introduced the Clean Energy Technology Manufacturing and Export Assistance Act of 2015, which would assist businesses with clean energy exports.

#21. Sen. Patty Murray

Ideology Score: 0.11

Washington Sen. Patty Murray co-sponsored the Electrify Africa Act of 2015, which was enacted in February 2016. The bill created a policy strategy to encourage sub-Saharan African countries to develop sustainable electrical power solutions.

#20. Rep. James P. McGovern

Ideology Score: 0.11

Rep. James “Jim” McGovern from Massachusetts introduced the Prescribe A Book Act, which planned to integrate reading and education into pediatric care. It has yet to move out of committee since January 2015. McGovern noted this early literacy program is backed by research that shows how “early exposure to reading goes a long way toward preparing children for school.”

#19. Rep. Charles B. Rangel

Ideology Score: 0.10

New York Rep. Charlie Rangel introduced the Veterans E-Health & Telemedicine Support Act of 2015, which aims to integrate telemedicine into the treatment of veterans. Telemedicine refers to the remote application of health care services through the use of telecommunications technology.

#18. Sen. Jeff Merkley

Ideology Score: 0.09

Oregon Sen. Jeff Merkley introduced the Stop Arctic Ocean Drilling Act of 2015, a bill that aimed to prohibit drilling in the Arctic Ocean. It has been stuck in committee since July 2015.

#17. Rep. Judy Chu

Ideology Score: 0.09

Rep. Judy Chu from California sponsored the Women’s Health Protection Act of 2015, which aimed to curtail restrictions on abortion services.

#16. Rep. Keith Ellison

Ideology Score: 0.09

Minnesota Rep. Keith Ellison introduced the Energy Efficient Manufactured Home Act of 2015, which proposed monetary incentives for replacing dated homes with Energy Star-qualified homes. This bill has yet to move out of committee.

#15. Rep. Michael M. Honda

Ideology Score: 0.09

Rep. Mike Honda, from California’s 17th District, introduced the Home-Assembled Firearms Restriction Act of 2015, which planned to prohibit the manufacturing, sale, distribution, importation and advertisement of firearm parts kits. It remains in a congressional committee since its referral in January 2015.

#14. Sen. Kirsten E. Gillibrand

Ideology Score: 0.08

New York Sen. Kirsten Gillibrand introduced the Microbead-Free Waters Act of 2015 to prohibit products that contain synthetic plastic microbeads, which are reportedly harmful to the environment. It was signed into law by President Obama on Dec. 28, 2015.

#13. Sen. Richard Blumenthal

Ideology Score: 0.08

Sen. Richard Blumenthal, the senior senator from Connecticut, introduced the Fairness to Pet Owners Act of 2015, which planned to give people the choice of where to purchase their pets’ medical prescriptions. The proposal has remained in committee since May 2015.

#12. Sen. Jack Reed

Ideology Score: 0.07

In March 2015, Rhode Island Sen. John “Jack” Reed proposed the Stop Illegal Insider Trading Act, which would have increased the restrictions on insider trading. The bill has yet to move out of committee. Reed explained: “Sharpening the definition of insider trading will clear up ambiguity in the law and help repair a broken system.”

#11. Sen. Barbara Boxer

Ideology Score: 0.07

Sen. Barbara Boxer from California introduced the End of Suffering Act of 2015, a right-to-die bill. When she introduced the legislation, Boxer said, “People suffering intolerable pain deserve autonomy in their health care decisions.” The bill remains in a congressional committee.

#10. Sen. Tammy Baldwin

Ideology Score: 0.07

Wisconsin Sen. Tammy Baldwin proposed the America’s College Promise Act of 2015. The bill, which remains in congressional committee, aimed to expand access to higher education by partnering with minority-serving institutions and making two years of community college free.

#9. Sen. Richard J. Durbin

Ideology Score: 0.07

Illinois Sen. Richard Durbin sponsored the Detergent PACS Act in February 2015. This bill addressed the danger of liquid detergent packs by creating new safety standards. It has yet to move out of its congressional committee.

#8. Sen. Sheldon Whitehouse

Ideology Score: 0.07

Rhode Island Sen. Sheldon Whitehouse introduced the National Oceans and Coastal Security Act. The bill, which remains in committee, planned to improve coastal infrastructure while promoting conservation efforts and ocean research.

#7. Sen. Al Franken

Ideology Score: 0.05

Sen. Al Franken co-sponsored the Mental Health Awareness and Improvement Act of 2015. Franken is a known advocate for mental health programs, as shown in a 2013 statement where he stated: “Nearly three-quarters of the kids in the country who suffer from mental health issues do not get the care they need, and that’s unacceptable.” The bill, which seeks to improve mental health and substance abuse-related programs, passed the Senate in December 2015 and awaits a House vote.

#6. Sen. Bernard Sanders

Ideology Score: 0.04

Vermont Sen. Bernie Sanders, a Democratic presidential candidate and the only Independent to make the list, introduced the Too Big To Fail, Too Big To Exist Act. This bill called for the Financial Stability Oversight Council to break up any banks deemed “too big to fail.” It has remained in committee since July 2015.

#5. Sen. Edward J. Markey

Ideology Score: 0.03

Sen. Ed Markey, a junior senator from Massachusetts, proposed the Oil Spill Deterrent Act. This bill proposed increasing penalties against oil companies that violate laws or regulations as a counter to the “speed-over-safety mentality that led to the Deepwater Horizon tragedy,” according to a press release from Markey’s office.

#4. Rep. Barbara Lee

Ideology Score: 0.03

California Rep. Barbara Lee proposed the Repeal of the Authorization for Use of Military Force Act. The bill, which has yet to leave committee, attempts to restore war-declaring abilities to Congress through eliminating open-ended military authorization.

#3. Rep. Eleanor Holmes Norton

Ideology Score: 0.01

Rep. Eleanor Holmes Norton, from D.C.’s At-Large District, introduced the LIFE Act. The bill proposes a national program to combat the number of overweight and obese Americans.

#2. Sen. Elizabeth Warren

Ideology Score: 0.00

Massachusetts Sen. Elizabeth Warren, the most liberal senator on this list, proposed the Schedules That Work Act. The bill, which has been in a congressional committee since July 2015, seeks to provide protections for employees who request changes to their work schedules.

Rep. Grijalva and Sen. Warren are tied as the most liberal with both having an “Ideology Score” of 0.

#1. Rep. Raul M. Grijalva

Ideology Score: 0.00

Arizona Rep. Raúl Grijalva, the most liberal member of the House on this list, introduced the Success in the Middle Act of 2015. This bill proposes grants to states that provide effective education models for students in middle school to help them prepare for high school. It has remained in congressional committee since April 2015.

Rep. Grijalva and Sen. Warren are tied as the most liberal with both having an “Ideology Score” of 0.