Democrat Mark Osmack has flipped a St. Louis County Council seat that Republicans held for more than a decade, beating GOP challenger Andrew Koenig in the District 3 race on Tuesday. Osmack took 54.85% of the vote to Koenig's 45.15%, according to unofficial results, continuing a years-long drift away from Republican dominance in the district.
The win was first reported by KSDK, which reported Osmack led Koenig by nearly 10 points once all precincts had reported, with Osmack collecting 36,829 votes to Koenig's 30,315 out of 67,144 total votes cast in the district. St. Louis Public Radio reported the same 54.85% to 45.15% split, describing Osmack as an Army veteran who works in the plumbing industry. All results remain unofficial, according to St. Louis County's election results page, which showed 200 of 200 polling places reporting.
Osmack is taking over the seat vacated by Republican Dennis Hancock, who opted not to seek reelection to the council and instead ran for county executive. That bid did not go well for Hancock: Democrat Jake Zimmerman defeated him by more than 30 points in the executive race, per KSDK's reporting. The council seat Hancock left behind has been trending away from his party for years, and St. Louis Public Radio's pre-election coverage laid out just how far. The outlet noted that Republican Colleen Wasinger beat Democrat Bob Nelson 63% to 37% in 2010 before running unopposed in 2014, and that Tim Fitch won by 8 points in 2018 — but when Hancock himself won the seat in 2022, his margin over Democrat Vicki Englund had shrunk to just 4 percentage points.
A District Stretching From Chesterfield to Jefferson County
District 3 covers a wide swath of the county, stretching from Chesterfield down to the border with Jefferson County, according to the same St. Louis Public Radio report previewing the race. In that pre-election coverage, Osmack said he wanted to streamline regulations and make it cheaper for residents to obtain necessary permits. Koenig, for his part, framed the county's budget struggles differently, telling the outlet, “It's basically a spending problem.”
Osmack's victory brings the council's partisan balance to five Democrats and two Republicans, expanding a majority that St. Louis Public Radio reported had already been building. Two other council members, Lisa Clancy and Rita Heard Days, ran unopposed for reelection this cycle, according to KSDK.
Other Races Decided Tuesday Night
Tuesday's election also settled a tighter contest in District 7, where Mark Harder defeated Democratic challenger John Kiehne by about 3 percentage points — a margin St. Louis Public Radio reported more precisely as 51% to 47%. Down the ballot, Melissa Price Smith won the prosecuting attorney race and Doug Clemens won the county assessor race, per KSDK's results coverage.
Taken together, the results reinforce a pattern St. Louis Public Radio's reporting has tracked for more than a decade: a county council district that was once a comfortable Republican hold has become genuinely competitive, and this year it tipped to the other side entirely.
