Daniel Biss is an American politician and mathematician who transitioned from academia into public service. He earned a PhD in mathematics from MIT and previously taught at the University of Chicago before entering politics. He began his political career in the Illinois House of Representatives (2011–2013), then served in the Illinois Senate (2013–2019), where he became known for work on budget policy, education, and economic reform. After leaving the state legislature, he ran for governor of Illinois in 2018, finishing second in the Democratic primary. In 2021, he was elected Mayor of Evanston, where he has focused on housing policy, climate initiatives, and local economic reforms. In 2026, he won the Democratic primary for Illinois’ 9th Congressional District and is the party’s nominee for the U.S. House seat.