Tea Party wave (2010)
Republicans flipped more than 20 state legislative chambers and Democrats lost over 700 seats. The gains came two years into Barack Obama's presidency and gave the GOP control of statehouses it had not held in decades.
Republicans passed abortion restrictions, loosened gun laws and expanded private-school vouchers.
The GOP drew congressional and state maps that helped hold power even in years Democrats won more statewide votes, a hold that lasted until 2026.
The 2026 midterms reversed the chamber advantage Republicans built in 2010, ending 16 years of GOP legislative dominance.
