Kamala Harris is extremely liberal — and the numbers prove it

Vice President Kamala Harris served in the Senate between 2017 and 2021, providing a legislative record that allows her to be located along the left-right continuum that dominates legislative behavior in the Congress. Based on her roll call voting record, Harris is the second-most liberal Democratic senator to serve in the Senate in the 21st century.

How do we know? For more than 40 years, political scientists have used roll call votes cast by members of Congress, combined with advanced statistical methods, to reliably plot the location of members of the House and Senate on the Liberal-Conservative/Left-Right dimension along which most legislative politics take place. (In Texas, I have conducted similar analysis of the Texas House of Representatives and Texas Senate biennially since 2011.)

The Voteview project (now based at UCLA) has, since the 1980s, employed the roll-call votes cast in Congress to locate all senators and representatives on a liberal-conservative ideological map. These data and methods have been utilized by academics in thousands of peer-reviewed books, book chapters and journal articles. Although no method is perfect, there is a general consensus within the academic community that the NOMINATE methodology employed by the Voteview project and its close cousins represent the gold standard.

The Voteview data can be used to study the Senate in two principal ways. The first method analyzes each two-year congressional period separately and provides a unique ideological location for every senator for each biennium, allowing for the comparison of senators who served during that Congress, but not for the comparison of senators across Congresses. The second method analyzes the congressional periods together and provides a single ideological location for a senator based on the entirety of their voting record while in that office, thereby allowing for the comparison of senators across Congresses.

Harris served in the Senate representing California during two Congresses (the 115th and 116th) before resigning to assume office as vice president in 2021.

In the 115th Congress (2017-2019), 48 Democrats served in the Senate and cast a sufficient number of votes for reliable analysis. Of those 48, Harris had the third-most liberal voting record, after Sen. Elizabeth Warren (Mass.) and Sen. Kirsten Gillibrand (N.Y.).

In the 116th Congress (2019-2020), 45 Democrats served in the Senate and cast a sufficient number of votes for reliable analysis. Of those 45, Harris had the second-most liberal voting record after Warren.

Since the turn of the century, there have been 11 complete Congresses (107th through 117th), with only five months remaining in the 118th. During this period, there were 109 different Democrats who served in the Senate and cast a sufficient number of roll call votes for a reliable analysis of their ideological position.

Of these 109 Democrats, Harris has the second-most liberal voting record. This makes her slightly less liberal than Warren, but more liberal than all of the remaining 107 Democrats, and significantly more liberal than all but a handful.

Included among these 109 Democrats are President Biden, former President Barack Obama and 2016 presidential nominee Hillary Clinton. The record indicates Clinton is more liberal than 74, Obama more liberal than 62 and Biden’s more liberal than 52.

Biden’s voting record locates him at the ideological center of these 109 Democratic senators (two senators to the right of the median Democratic senator). Obama’s record locates him pretty close to the Democratic ideological center as well (eight senators to the left of the median Democratic senator). Clinton’s record locates her in the Democratic center-left (20 senators to the left of the median Democratic senator).

In sharp contrast, Harris’s roll call record places her on the far-left ideological edge of this cohort of Democratic senators (53 senators to the left of the median Democratic senator).

Roll-call votes represent only one of several different metrics that can be utilized to evaluate the ideological orientation of politicians. In the case of Harris, based solely on the votes which she cast during her four years in the Senate, rigorous extant academic analysis locates her as one of the Senate’s very most liberal members, with a voting record substantially to the left of virtually all Senate Democrats, past and present.

Mark P. Jones is the James A. Baker III Institute for Public Policy’s fellow in political science and co-director of its Presidential Elections Program, as well as the Joseph D. Jamail Chair in Latin American Studies at Rice University.