House Democrats Reclaim 104th District With Mary Catherine Roberson’s Victory Over Republican Incumbent
Strategic Investment and a Strong Democratic Candidate Deliver Major Victory as House Democrats Expand Historic Supermajority
CHICAGO, IL — Democrats for the Illinois House (DIH) is celebrating another significant victory in the 2026 General Election as Democratic challenger Mary Catherine Roberson successfully flipped a downstate swing district, defeating Republican incumbent Brandun Schweizer and returning the seat to Democratic control.
Schweizer conceded to Roberson on November 4, growing the historic House Democratic majority to 85–the largest in modern state history. The win marks a major victory for House Democrats and underscores the effectiveness of DIH’s strategic investment and aggressive campaign operation.
Roberson’s 104th District was a particularly important target for House Democrats after losing the seat to Schweizer in the previous election cycle. Rather than accepting the district as a Republican stronghold, DIH identified a path to reclaim it and committed the resources necessary to turn that opportunity into a victory.
Through strategic polling, targeted investment, and a disciplined campaign strategy, House Democrats recognized the district’s potential and backed Roberson with the support necessary to compete against an entrenched Republican incumbent.
The victory reflects DIH’s broader commitment to expanding the Democratic electoral map while protecting its existing majority. With millions raised during the 2026 election cycle, House Democrats built a comprehensive campaign operation focused on defending incumbents, recruiting competitive challengers, and investing in districts where strategic opportunities existed.
Roberson’s win also shows the importance of sustained investment in districts long considered Republican. By refusing to concede competitive territory and instead making data-driven decisions about where to deploy resources, DIH successfully turned a Republican-held seat into another Democratic victory.
Roberson’s victory is part of yet another historic election cycle for Illinois House Democrats, who have flipped six Republican-held seats while protecting their incumbents and expanding one of the nation’s strongest Democratic legislative majorities.
As House Democrats prepare for the next legislative session, the caucus remains focused on delivering results for Illinois families, investing in education, lowering costs, strengthening communities, and building an economy that works for everyone.
“Mary Catherine Roberson earned this victory through hard work, determination, and a commitment to the people of her district,” Speaker Welch said. “We are proud to welcome her to the Illinois House Democratic Caucus, and we look forward to the leadership she will bring to Springfield.”