Missouri narrowly avoided a constitutional crisis after Secretary of State Denny Hoskins rejected a referendum petition challenging H.B. 1, a redistricting bill eliminating a Democratic congressional seat. Passed in September 2025, H.B. 1 was part of a national redistricting wave sparked after President Trump pressured Texas to redraw maps for Republican advantage, potentially netting the GOP 10 House seats.

Denny Hoskins, a Republican, waited until one hour before the Aug. 4, 2026 deadline — coinciding with state primaries — to reject over 300,000 valid signatures. He claimed the Missouri Constitution barred referendums on redistricting, a novel legal theory. The Missouri Supreme Court unanimously ruled Sept. 3 that voters could overturn redistricting via referendum, declaring H.B. 1 "not the law and has never been the law."

Missouri appealed to the U.S. Supreme Court, but Justice Brett Kavanaugh denied a stay on Sept. 8, affirming state court authority over state law. The referendum will appear on the November ballot, restoring the previous congressional map for the midterms.