Democrat Renee Hardman won Iowa's Senate District 16 special election on Dec. 31, 2025, flipping a GOP-leaning seat.

On December 31, 2025, a special election was held in Iowa's Senate District 16, and Democrat Renee Hardman defeated Republican Brad H. Johnson with roughly 52% of the vote. In a state where Republicans predominate, the victory in a historically Republican-leaning district represents a rare Democratic victory and keeps the GOP from regaining a supermajority in the 50-member Senate. The race's importance as a bellwether ahead of the 2026 elections was highlighted by the high turnout, which was fueled by early voting and increased participation from younger and suburban voters.