1806–07 United States Senate elections#Connecticut

{{Infobox election

| election_name = 1806–07 United States Senate elections

| country = United States

| flag_year = 1795

| type = legislative

| ongoing = no

| previous_election = 1804–05 United States Senate elections

| previous_year = {{Nowrap|1804 & 1805}}

| next_election = 1808–09 United States Senate elections

| next_year = {{Nowrap|1808 & 1809}}

| seats_for_election = 11 of the 34 seats in the United States Senate (plus special elections)

| majority_seats = 18

| election_date = Dates vary by state

| image_size = 100px

| 1blank = Seats up

| image1 =

| party1 = Democratic-Republican Party

| last_election1 = 27 seats

| seats_before1 = 27

| seats1 = 10

| seats_after1 = 28

| seat_change1 = {{increase}} 1

| 1data1 = 9

| image2 =

| party2 = Federalist Party

| last_election2 = 7 seats

| seats_before2 = 7

| seats2 = 1

| seats_after2 = 6

| seat_change2 = {{decrease}} 1

| 1data2 = 2

| title = Majority Party

| before_election =

| before_party = Democratic-Republican Party

| after_election =

| after_party = Democratic-Republican Party

| map_image = File:1806senatemap.svg

| map_caption = Results:
{{Legend0|#bef3be|Dem-Republican hold}} {{legend0|#008000|Dem-Republican gain}}
{{Legend0|#f2bfa6|Federalist hold}}

}}

The 1806–07 United States Senate elections were held on various dates in various states. As these U.S. Senate elections were prior to the ratification of the Seventeenth Amendment in 1913, senators were chosen by state legislatures. Senators were elected over a wide range of time throughout 1806 and 1807, and a seat may have been filled months late or remained vacant due to legislative deadlock.{{cite web|url=https://www.archives.gov/milestone-documents/17th-amendment|title=17th Amendment to the U.S. Constitution: Direct Election of U.S. Senators (1913)|website=National Archives and Records Administration|date=February 8, 2022}} In these elections, terms were up for the senators in Class 3.

The Democratic-Republican Party increased its overwhelming control of the Senate by one additional seat. The Federalists went into the elections with such a small share of Senate seats (7 out of 34, or 21%) that even if they had won every election, they would still have remained a minority caucus. As it was, however, they lost one of the two seats they were defending and picked up no gains from their opponents.

Results summary

Senate party division, 10th Congress (1807–1809)

Majority party: Democratic-Republican (28)
Minority party: Federalist (6)
Other parties: 0
Total seats: 34

Change in composition

= Before the elections =

class="wikitable" style="text-align:center" width=800px

{{Party shading/Democratic-Republican}} | DR{{Sub|7}}

| {{Party shading/Democratic-Republican}} | DR{{Sub|6}}

| {{Party shading/Democratic-Republican}} | DR{{Sub|5}}

| {{Party shading/Democratic-Republican}} | DR{{Sub|4}}

| {{Party shading/Democratic-Republican}} | DR{{Sub|3}}

| {{Party shading/Democratic-Republican}} | DR{{Sub|2}}

| {{Party shading/Democratic-Republican}} | DR{{Sub|1}}

width=50px {{Party shading/Democratic-Republican}} | DR{{Sub|8}}

| width=50px {{Party shading/Democratic-Republican}} | DR{{Sub|9}}

| width=50px {{Party shading/Democratic-Republican}} | DR{{Sub|10}}

| width=50px {{Party shading/Democratic-Republican}} | DR{{Sub|11}}

| width=50px {{Party shading/Democratic-Republican}} | DR{{Sub|12}}

| width=50px {{Party shading/Democratic-Republican}} | DR{{Sub|13}}

| width=50px {{Party shading/Democratic-Republican}} | DR{{Sub|14}}

| width=50px {{Party shading/Democratic-Republican}} | DR{{Sub|15}}

| width=50px {{Party shading/Democratic-Republican}} | DR{{Sub|16}}

| width=50px {{Party shading/Democratic-Republican}} | DR{{Sub|17}}

colspan=9 style="text-align:right" | Majority →

| rowspan=2 {{Party shading/Democratic-Republican}} | DR{{Sub|18}}

{{Party shading/Democratic-Republican/active}} | DR{{Sub|27}}
{{Small|Pa.}}
{{Small|Retired}}

| {{Party shading/Democratic-Republican/active}} | DR{{Sub|26}}
{{Small|N.C.}}
{{Small|Retired}}

| {{Party shading/Democratic-Republican/active}} | DR{{Sub|25}}
{{Small|Ohio}}
{{Small|Unknown}}

| {{Party shading/Democratic-Republican/active}} | DR{{Sub|24}}
{{Small|Vt.}}
{{Small|Ran}}

| {{Party shading/Democratic-Republican/active}} | DR{{Sub|23}}
{{Small|S.C.}}
{{Small|Ran}}

| {{Party shading/Democratic-Republican/active}} | DR{{Sub|22}}
{{Small|N.Y.}}
{{Small|Ran}}

| {{Party shading/Democratic-Republican/active}} | DR{{Sub|21}}
{{Small|Md.}}
{{Small|Ran}}

| {{Party shading/Democratic-Republican/active}} | DR{{Sub|20}}
{{Small|Ky.}}
{{Small|Ran}}

| {{Party shading/Democratic-Republican/active}} | DR{{Sub|19}}
{{Small|Ga.}}
{{Small|Ran}}

{{Party shading/Federalist/active}} | F{{Sub|7}}
{{Small|N.H.}}
{{Small|Retired}}

| {{Party shading/Federalist/active}} | F{{Sub|6}}
{{Small|Conn.}}
{{Small|Ran}}

| {{Party shading/Federalist}} | F{{Sub|5}}

| {{Party shading/Federalist}} | F{{Sub|4}}

| {{Party shading/Federalist}} | F{{Sub|3}}

| {{Party shading/Federalist}} | F{{Sub|2}}

| {{Party shading/Federalist}} | F{{Sub|1}}

= Beginning of the next Congress =