The seats that change party most often

The U.S. Senate seats and governorships that have switched between the parties more than any others, election to election.

The governorship of Rhode Island has changed party more often than any other office in the dataset: 45 times, across 154 elections from 1797 to 2022. Massachusetts (40) and Ohio (39) follow. Among U.S. Senate seats the most-flipped is Minnesota, with 9, across 18 elections from 1918 to 2020. A flip is counted when one regular election for a seat is won by a different party from the last one, so it measures turnover rather than the size of any single win.

Which Senate seat changes party most often?

Minnesota, with 9 flips across 18 elections from 1918 to 2020. Ohio (9) and Iowa (8) are next. Each state’s two seats are counted separately, by class, so a genuinely competitive seat is never averaged against the safe one beside it.

Why are governorships and Senate seats ranked separately?

Because they do not face the voters at the same rate. Many states elected a governor every year or every two years in the nineteenth century, so a governorship can log 150 elections where a Senate seat has logged 18. Ranking them together would produce a list of nothing but governorships.

How is a party flip counted?

By comparing consecutive regular elections for the same seat. When the winning party differs from the previous election’s, that is one flip. Special elections are excluded because they fall off the seat’s normal cycle.

Why are the two Senate seats in a state counted separately?

Because they are different seats, elected in different years. Senate seats are grouped in three classes on a six-year rotation, and mixing a state’s two seats together would show flips that never happened.

Governorships

The seats that change party most often
#	Seat	Party flips	Held now by	Elections
1	Rhode Island	45	D	1797–2022 154
2	Massachusetts	40	D	1789–2022 157
3	Ohio	39	R	1803–2022 95
4	Connecticut	36	D	1789–2022 142
5	New Hampshire	32	R	1789–2024 162
6	Pennsylvania	30	D	1790–2022 67
7	New Jersey	30	D	1789–2025 107
8	Maine	28	D	1820–2022 115
9	Maryland	27	D	1789–2022 94
10	Colorado	25	D	1876–2022 58
11	New York	25	D	1789–2022 68
12	Kansas	25	D	1859–2022 70
13	Delaware	24	D	1792–2024 61
14	Michigan	24	D	1835–2022 81
15	Tennessee	24	R	1799–2022 86
16	California	23	D	1849–2022 48
17	Wisconsin	23	D	1848–2022 75
18	Vermont	23	R	1793–2024 154
19	Kentucky	22	D	1800–2023 57
20	Minnesota	22	D	1857–2022 68
21	Indiana	21	R	1816–2024 56
22	Illinois	20	D	1818–2022 53
23	Nebraska	20	R	1866–2022 65
24	North Carolina	20	D	1789–2024 102
25	West Virginia	19	R	1863–2024 44

U.S. Senate seats

Counted by class, so a state’s two seats are never mixed together.

The seats that change party most often
#	Seat	Party flips	Held now by	Elections
1	Minnesota	9	D	1918–2020 18
2	Ohio	9	R	1916–2024 19
3	Iowa	8	R	1918–2020 18
4	Colorado	8	D	1914–2022 19
5	Indiana	8	R	1916–2024 19
6	Colorado	7	D	1918–2020 18
7	Indiana	7	R	1914–2022 18
8	Oklahoma	7	R	1918–2020 18
9	California	7	D	1916–2024 19
10	Connecticut	7	D	1916–2024 19
11	Maryland	7	D	1916–2024 19
12	Missouri	7	R	1916–2024 19
13	Wisconsin	7	R	1914–2022 19
14	South Dakota	6	R	1918–2020 18
15	Wyoming	6	R	1918–2020 18
16	Maryland	6	D	1914–2022 19
17	Minnesota	6	D	1916–2024 19
18	Nevada	6	D	1916–2024 19
19	New York	6	D	1916–2024 19
20	Ohio	6	R	1914–2022 19
21	Oregon	6	D	1914–2022 19
22	Connecticut	5	D	1914–2016 18
23	Delaware	5	D	1918–2020 18
24	Illinois	5	D	1914–2022 18
25	Illinois	5	D	1918–2020 18

How this ranking is measured

A flip is a regular general election for a seat won by a different party from the one that won the previous regular election for that same seat. U.S. Senate seats are separated by class — the three groups elected in different even years on a six-year rotation — so a state’s two seats are never mixed. Special elections and recalls are excluded: they fall outside the cycle and would land a seat in the wrong class. Wins on a New York or Connecticut cross-endorsement line count for the major party the candidate belongs to. Elections won by parties that no longer exist count as flips in and out of "other".

Compiled by PolitiFinder · published June 14, 2026 · sources: Data & sources · data last verified September 9, 2026.