Senators Ranked by Legislative Effectiveness Score: The CEL Data

What the score measures, and what it refuses to measure

The Legislative Effectiveness Score is the closest thing American political science has to a batting average for lawmakers. Built by Craig Volden and Alan Wiseman, it tracks fifteen data points per member: every sponsored bill, weighted by how substantive it is and how far it travels, from introduction through committee, chamber passage, and enactment (CEL Methodology; CEL, 118th Congress Highlights, 2025). It does not count tweets, cable appearances, fundraising, or floor speeches. A senator who dominates the news and enacts nothing scores near zero. That is a design choice, and it is the correct one for this site: only actions matter.

The 118th Congress release, CEL's fifth biennial Senate assessment in its current form, landed in March 2025 and covered a Congress remembered for gridlock. CEL's headline finding was that lawmaking continued anyway, increasingly through language quietly attached to must-pass vehicles like the annual defense authorization and omnibus appropriations packages (Vanderbilt University, March 27, 2025). The underlying dataset reaches back to 1973, which is what allows CEL to say with evidence, rather than nostalgia, that the influence of committee chairs has declined: chairs in the 118th House averaged about one enacted sponsored bill each, the lowest rate the project has recorded across five decades (CEL, 118th Congress Highlights, 2025).

The Peters anomaly

Gary Peters scored 10.648. The Senate average is normalized to 1.0. The gap between Peters and second place, John Cornyn at 6.562, is larger than the gap between Cornyn and the fiftieth senator. CEL notes a distinction no other current senator holds: in the 116th Congress Peters posted the Senate's highest score while in the minority party, a feat found nowhere else in CEL's data, which reaches back to 1973 (CEL, 118th Congress Highlights, 2025).

The mechanics are documented. Nearly every Peters bill that became law carried at least one Republican cosponsor, and some carried only Republican cosponsors. CEL's long-run research finding is blunt: bipartisan lawmakers outperform partisan ones even when their party holds the majority (CEL, 2025). Peters, who chaired Homeland Security and Governmental Affairs, is the proof case.

Who left the leaderboard

Five senators in the published 118th top-ten tables no longer serve, and CEL itself flagged the drain: high performers keep leaving through retirement, lost elections, or the executive branch. Jon Tester (LES 1.963, fourth among Democrats) lost reelection. Tom Carper (1.719) retired. Bob Menendez (1.443) resigned. Marco Rubio (2.638, second among Republicans) became Secretary of State. Mike Braun (1.767, fourth among Republicans) became governor of Indiana (CEL, 118th Congress Highlights, 2025; Senate roster, July 2026). The 119th Congress therefore began with a measurable effectiveness vacuum, and the next CEL release will show who filled it.

From score to statute: what the top scorers actually passed

The scores summarize documented bill trajectories, and the trajectories are worth seeing raw. Peters introduced 152 bills; 34 passed the Senate and 15 became law as standalone measures, with substantial language from roughly ten more incorporated into other members' bills that were enacted, including the Defense Support for Cyber Emergencies Response Act (CEL, 118th Congress Highlights, 2025). Cornyn introduced 107 bills, passed 21 through the Senate, and enacted 7 standalone laws, mostly judicial and legal measures such as the Improving Access to Our Courts Act, while placing language from 12 more bills, largely armed services and national security matters, into vehicles like the Fiscal Year 2024 National Defense Authorization Act (CEL, 2025). Klobuchar introduced 116 bills across a deliberately wide policy range, with 6 passing the Senate and 3 enacted. Padilla sponsored 92 bills, passed 9, enacted 2, and had three more substantially carried into law, including the Fusion Energy Act of 2024 and the Office of Disaster Recovery and Resilience Act (Padilla Senate office, 2025).

Two different playbooks are visible in those numbers. Peters runs a high-conversion operation: fewer wasted bills, heavy bipartisan cosponsorship, standalone enactments. Cornyn runs a two-track operation: a standalone track in his committee wheelhouse and an incorporation track that rides must-pass vehicles. CEL's report treats the second track as fully legitimate lawmaking, because the policy becomes law either way, and this site agrees: the statute books do not record whether a provision arrived on its own cover page (CEL, 2025).

Reading the scores honestly

Three cautions come from CEL's own methodology. First, majority status matters: 118th Senate majority members averaged 1.11 against 0.88 for the minority, which is why CEL ranks within parties and this report preserves that structure. Second, committee chairs average 1.51, so a chairmanship is an engine of the score, not a bias in it; the score measures institutional position plus skill. Third, the benchmark system exists precisely so a talented backbencher is not judged against a chair: Exceeds Expectations means beating the score predicted for that member's seniority, party status, and position by 50 percent or more (CEL, 2025). Cornyn, Rubio, and Peters held the longest active streaks in that category, and the top three first-term senators in it were Padilla, Braun, and Rosen (CEL, 2025). If a reader's favorite senator is absent from this table, the explanation is arithmetic, not editorial.

One more caution belongs to the calendar. These scores describe the 118th Congress, which ended in January 2025. Senators change: chairs rotate, majorities flip, and the 119th Congress installed a new Republican majority whose scores will not be published until after it ends. A ranking that pretended to know the current Congress's effectiveness before CEL scores it would be guessing, and this site does not guess. The 118th data is the most recent truth available, presented as exactly that (CEL, 2025).