by Todd Feurer, CBS Chicago web producerBy CBS 2 Chicago Staff

CHICAGO (CBS) — State Sen. Heather Steans (D-Chicago), who was instrumental in the passage of legislation legalizing recreational marijuana and same-sex marriage in Illinois, is resigning from office at the end of the month.

“It’s been the privilege of a lifetime to represent the most diverse Senate district in the State of Illinois,” Steans said. “I’ve benefited tremendously from the many perspectives of the people a I’ve represented. We’ve made great progress together, and now it’s time to pass the baton.”

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A spokesperson for Illinois State Rep. Kelly Cassidy (D-Chicago), who represents half of Steans’ Senate district in the Illinois House, said Cassidy would seek to be appointed to the Steans’ seat for the rest of her term.

Illinois House Majority Leader Greg Harris (D-Chicago), who represents the other half of Steans’ district in the Illinois House, said he won’t seek the appointment.

“I want to thank Sen. Heather Steans for 12 years of service to the people of Illinois, and for being chief Senate sponsor of Marriage Equality in Illinois, a tireless fighter for immigrant/refugee rights, a woman’s right to choose and access to quality healthcare for all. You have made so much change happen for so many,” he wrote in an email.

A state senator for Chicago’s North Side since 2009, Steans sponsored the 2013 law allowing same sex couples to marry in Illinois, a 2017 measure expanding abortion coverage for women on Medicaid or state insurance plans, as well as the 2019 law legalizing recreational use of marijuana in the state.

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“For every significant piece of legislation expanding women’s or LGBTQ rights in the past 12 years, Heather has been a leading voice,” said Terry Cosgrove, President and CEO of Personal PAC. “Her fingerprints are all over the tremendous gains we’ve made in Illinois in ensuring that our fundamental rights are protected.”

Illinois Senate President Don Harmon (D-Oak Park) said Steans “forever changed this state for the better.”

“People across Illinois had their rights recognized and protected thanks to her leadership. She is a forceful advocate for progress and problem solving, who fearlessly tackled many of the biggest issues in our society and was always looking for her next challenge. I wish her the best in her next adventures and thank her for all she has done for the Senate and the great state of Illinois,” Harmon said in a statement.

Steans’ resignation takes effect Jan. 31. Democratic committeemen in her district will vote on the appointment of someone to fill her seat for the rest of her term, which expires in January 2023.

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