1848 and 1849 United States House of Representatives elections Information
All 233 [b] seats in the U.S. House of Representatives
117 seats needed for a majority
These elections spanned the presidential election of 1848 and took place amid the U.S. victory over Mexico in the (1846–48) Mexican–American War. The Whigs lost their House majority as Democrats, whose support had driven the war, gained a House plurality. Among minor parties, the Free Soil Party won nine Northern seats, while the American or " Know Nothing" Party retained one.
Following the discovery of gold in January 1848, California boomed, creating immediate pressure for statehood. The Compromise of 1850, though largely crafted in the Senate, was also passed by the House, brokering its admission to the Union. Anticipating statehood, California elected two Representatives at-large on November 11, 1849, to be seated September 11, 1850.
As neither major party held a majority when Congress convened on December 3, 1849, the election of a Speaker proved contentious. The Whigs split, with Northern Whigs nominating incumbent speaker Robert C. Winthrop of Massachusetts and Southern Whigs supporting Meredith P. Gentry of Tennessee. Although Democrats primarily supported Howell Cobb of Georgia, over a dozen other candidates also garnered support. Anti-slavery Free Soilers supported David Wilmot of Pennsylvania, author of the Wilmot Proviso, calling attention to Slave Power's hold over both major parties. After nearly three weeks of heated debate, the House suspended its majority rule for the Speaker election. Cobb was elected on the 63rd ballot by plurality. 
|Arkansas||At-large||August 7, 1848||1||1||0||0||0|
|Illinois||District||August 7, 1848||7||6||0||1||0|
|Iowa||District||August 7, 1848||2||2||0||0||0|
|Missouri||District||August 7, 1848||5||5||0||0||0|
|Vermont||District||September 5, 1848||4||1||0||3||0|
|Maine||District||September 11, 1848||7||5||1||0||2||1||0|
|Florida||At-large||October 2, 1848||1||0||0||1||0|
|Georgia||District||October 2, 1848||8||4||0||4||0|
|South Carolina||District||October 9–10, 1848||7||7||0||0||0|
|Ohio||District||October 10, 1848||21||11||1||2||2||8||3||0|
|Pennsylvania||District||October 10, 1848||24||9||2||1||1||13||3||1 [d]|
|Delaware||At-large||November 6, 1848||1||0||0||1||0|
|Michigan||District||November 7, 1848
( Election Day) [e]
|Massachusetts||District||November 13, 1848||10 [g]||0||1||1||8||2||0|
|New Hampshire||District||March 13, 1849||4||2||1||1||1||0||1 [h]|
|Connecticut||District||April 2, 1849||4||2||2||1||1||1||3||0|
|Rhode Island||District||April 4, 1849||2||0||1||0||2||1||0|
|Virginia||District||April 26, 1849||15||13||4||0||2||4||0|
|Tennessee||District||August 2, 1849||11||7||1||0||4||1||0|
|Alabama||District||August 6, 1849||7||5||0||2||0|
|Indiana||District||August 6, 1849||10||8||2||1||1||1||3||0|
|Kentucky||District||August 6, 1849||10||4||0||6||0|
|Texas||District||August 6, 1849||2||2||0||0||0|
|North Carolina||District||August 7, 1849||9||3||0||6||0|
|Maryland||District||October 3, 1849||6||3||1||0||3||1||0|
|Louisiana||District||November 5, 1849||4||3||0||1||0|
|Mississippi||District||November 5–6, 1849||4||4||1||0||0||1||0|
|California||At-large||November 11, 1849 [i]||2||1||1||0||0||1 [j]||1|
California two at-large members were elected November 11, 1849 in anticipation of statehood.
2 seats on a general ticket
New member elected.
New member elected.
Florida's single at-large member was elected October 2, 1848.
|Florida at-large||Edward C. Cabell||Whig||1846||Incumbent re-elected.|
|Minnesota Territory||None. New territory||New seat.
New delegate elected July 7, 1849.
- 1848 United States elections
- 30th United States Congress
- 31st United States Congress
- Excludes states admitted during the 31st Congress
- Includes late elections
- There were 9 Free Soilers, 1 Know Nothing, and 1 Independent.
- 1 Know Nothing
- In 1845, Congress passed a law providing for a uniform date for choosing presidential electors (see: Statutes at Large, 28th Congress, 2nd Session, p. 721). Congressional elections were unaffected by this law, but the date was gradually adopted by the states for Congressional elections as well.
- Increase of 1 seat.
- One vacancy, in MA-04, for the duration of the 31st Congress (as no candidate received a majority of the vote after multiple elections).
- Previous election had 1 Independent.
- Seated September 11, 1850 after admission to the Union.
- 1 Independent elected.
- Dubin, Michael J. (March 1, 1998). United States Congressional Elections, 1788-1997: The Official Results of the Elections of the 1st Through 105th Congresses. McFarland and Company. ISBN 978-0786402830.
- Martis, Kenneth C. (January 1, 1989). The Historical Atlas of Political Parties in the United States Congress, 1789-1989. Macmillan Publishing Company. ISBN 978-0029201701.
- Moore, John L., ed. (1994). Congressional Quarterly's Guide to U.S. Elections (Third ed.). Congressional Quarterly Inc. ISBN 978-0871879967.
- "Party Divisions of the House of Representatives* 1789–Present". Office of the Historian, House of United States House of Representatives. Retrieved January 21, 2015.
- Office of the Historian (Office of Art & Archives, Office of the Clerk, U.S. House of Representatives)