| ← 1856 1857 1858 1859 1860 → Midterm elections | |
| Incumbent president | James Buchanan (Democratic) |
|---|---|
| Next Congress | 36th |
| Senate elections | |
| Overall control | Democratic hold |
| Seats contested | 22 of 66 seats [1] |
| Net seat change | Republican +5 [2] |
| House elections | |
| Overall control | Republican gain |
| Seats contested | All 238 voting seats |
| Net seat change | Republican +23 [2] |
 | |
| 1858 House of Representatives election net gains by state 6+ Republican gain 3 to 5 Republican gain 1 to 2 Republican gain 1 to 2 Democratic gain Territory | |
Elections occurred in the middle of Democratic President James Buchanan's term and marked the end of the transitional period between the Second Party System and the Third Party System. [3] Members of the 36th United States Congress were chosen in this election. In the first election since the Supreme Court decided Dred Scott v. Sandford , the Republican Party won a plurality in the House, taking control of a chamber of Congress for the first time in the party's history. Although Democrats lost control of the House, they retained their majority in the Senate.
In the House, Democrats suffered a major defeat, losing seats to Republicans and a group of southern party members who opposed secession, running on the Opposition Party ticket. Although no party won a majority, Republicans won a plurality of seats. [4] Republican William Pennington won election as Speaker of the House, becoming the first Republican Speaker.
In the Senate, Republicans picked up several seats, but Democrats retained a commanding majority. Nonetheless the gains were a major win for Republicans who had benefitted from the fallout of the Dred Scott ruling. [5]
