Daniel K. Biss

DMayor of Evanston (since 2021)

Daniel Biss is the Democratic nominee for the open Illinois 9th District seat. A former state legislator and current mayor of Evanston, he won the crowded March 2026 Democratic primary.[1][2]

Basic profile — the most important sourced facts we found.

On the record — official actions

  • actionChaired the Illinois Senate Human Services Committee in the 2015 legislative session and the Labor Committee in the 2017 session.[3]

Positions on the issues

  • SupportsProtect legal access to abortion

    Says he has passed legislation preserving access to abortion and would continue to stand up for it in Congress.[2]

  • OpposesExpand immigration enforcement and deportations

    Says he would stand up to the Trump administration on immigration.[2]

  • SupportsFaster transition away from fossil fuels

    Cites having passed stricter carbon-efficiency standards for buildings as a state legislator.[2]

In their words — priorities

  • Says he has a record of passing legislation preserving access to abortion, changing campaign finance law, and setting stricter carbon-efficiency standards for buildings while in the state legislature and as mayor.[2]
  • Says he would stand up to President Trump on immigration, preserving access to abortion, and expanding mental health services.[2]

Background

  • Earned a bachelor's degree in mathematics from Harvard University and a doctorate in mathematics from the Massachusetts Institute of Technology.[2]
  • Worked as a math professor at the University of Chicago before entering elected politics.[2]
  • Served in the Illinois House of Representatives (2011–2013) and Illinois Senate (2013–2019) before being elected mayor of Evanston in 2021.[2][3]
  • Chaired the Illinois Senate Human Services Committee in the 2015 session and the Labor Committee in the 2017 session.[3]

Campaign money

Raised $2.9M · spent $2.7M · $262K cash on hand (through 2026-06-30) FEC filing ↗

Also on the ballot for this seat: John Elleson · Compare side by side

Sources cited in this profile

  1. 1.Illinois' 9th Congressional District election, 2026 · Ballotpedia · 2026-09-25 Reference
  2. 2.Daniel K. Biss candidate profile · Ballotpedia (compiled from Biss campaign materials) · 2026-09-25 Candidate's own words
  3. 3.Daniel Biss · Ballotpedia · 2026-09-25 Reference