The redrawn boundaries for Ohio’s 9th congressional district, approved in late 2025 to favor Republicans, have narrowed the margin for long-serving Democratic incumbent Marcy Kaptur, who won her May 5 primary without opposition. Republican nominee Derek Merrin, who came within roughly 2,400 votes of victory in 2024, secured his nomination on the same date after a competitive primary, yet the race remains closely contested. Traders assign the Democratic nominee a 67.5 percent implied probability largely because of Kaptur’s decades of incumbency advantage, established constituent relationships, and the district’s historical voting patterns that have resisted similar map changes in prior cycles. No major new developments have shifted these assessments in the past two weeks.