| Election Name: | 2020 Maine Senate election |
| Country: | Maine |
| Type: | legislative |
| Ongoing: | no |
| Previous Election: | 2018 Maine Senate election |
| Previous Year: | 2018 |
| Next Election: | 2022 Maine Senate election |
| Next Year: | 2022 |
| Seats For Election: | All 35 seats in the Maine Senate |
| Majority Seats: | 18 |
| Election Date: | November 3, 2020 |
| Leader1: | Troy Jackson |
| Party1: | Democratic Party (United States) |
| Leaders Seat1: | 1st |
| Seats Before1: | 21 |
| Seats1: | 22 |
| Seat Change1: | 1 |
| Popular Vote1: | 418,062 |
| Percentage1: | 52.9% |
| Swing1: | 3.0% |
| Leader2: | Dana Dow |
| Party2: | Republican Party (United States) |
| Leaders Seat2: | 13th (lost re-election) |
| Seats Before2: | 14 |
| Seats2: | 13 |
| Seat Change2: | 1 |
| Popular Vote2: | 369,474 |
| Percentage2: | 46.7% |
| Swing2: | 3.5% |
| Map Size: | 300px |
| Senate President | |
| Before Election: | Troy Jackson |
| Before Party: | Democratic |
| After Election: | Troy Jackson |
| After Party: | Democratic |
The 2020 Maine State Senate election was held on Tuesday, November 3, 2020, with the primary election using instant-runoff voting being held on July 14, 2020, to elect the 130th Maine Senate. Voters in all 35 districts of the Maine State Senate will elect their senators. The elections will coincide with the elections for other offices, including for U.S. President, U.S. Senate, U.S. House and the Maine House of Representatives. Republicans only needed to gain four seats to win control of the chamber; they instead gained only one and lost another two, resulting in a net increase in the Democratic Party's majority.
The primary elections were held on July 14, 2020.
In the 2018 Maine State Senate elections, Democrats gained control of Maine State Senate by a 21–14 margin. Before those elections, Republicans had controlled the chamber since 2014 Maine State Senate elections.
| 22 | 13 | |
| Democratic | Republican |
| Candidates | Popular Vote | Seats | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| align=center | Vote | align=center | % | align=center | 2018 | align=center | 2020 | align=center | +/− | align=center | Strength | |||||
| Democratic | align=center | 35 | align=right | 418,062 | align=right | 52.85% | align=center | 21 | align=center | 22 | align=center | 1 | align=right | 62.86% | ||
| Republican | align=center | 33 | align=right | 369,474 | align=right | 46.71% | align=center | 14 | align=center | 13 | align=center | 1 | align=right | 37.14% | ||
| Independent | align=center | 2 | align=right | 3,479 | align=right | 0.44% | align=center | 0 | align=center | 0 | align=center | align=right | 0.00% | |||
| align=center colspan="2" | Total | align=center | 70 | align=center | 791,015 | align=center | 100.00% | align=center | 35 | align=center | 35 | align=center | align=center | 100.00% |
Seats where the margin of victory was under 10%:
| align=center | District 1 • District 2 • District 3 • District 4 • District 5 • District 6 • District 7 • District 8 • District 9 • District 10 • District 11 • District 12 • District 13 • District 14 • District 15 • District 16 • District 17 • District 18 • District 19 • District 20 • District 21 • District 22 • District 23 • District 24 • District 25 • District 26 • District 27 • District 28 • District 29 • District 30 • District 31 • District 32 • District 33 • District 34 • District 35 |
See main article: e.