Elections / 2004 · US Senate
The 2004 Senate map
34 Senate contests were decided in 2004: Democrats won 15, Republicans 19. Every contest below links to its page with the state's full Senate history.
2004 U.S. Senate elections
Dem. caucus 45 −451for control55 Republicans +4
7 seats flipped (CO, FL, IL, LA, NC, SC, SD) — Republicans held control. Independents (Sanders, King) are counted in the caucus they organize with and shown in gold on the map.
VTNHCTMD
States with a seat up this cycle, filled by margin · cyan outlines a seat that flipped party · gold an independent · hover for the detail
Every contest
Statewide totals; candidate-level detail joins when the raw store is re-fetched with names.
| State | Won | Margin | Pres. 2004 | Democratic | Republican | Total |
|---|---|---|---|---|---|---|
| Alaska | R | R+25.9 | 140,424 | 149,773 | 307,892 | |
| Alabama | R | R+25.6 | 595,018 | 1,242,200 | 1,837,218 | |
| Arkansas | D | R+9.8 | 580,973 | 458,036 | 1,039,221 | |
| Arizona | R | R+10.5 | 404,507 | 1,505,372 | 1,961,677 | |
| California | D | D+9.9 | 6,955,728 | 4,555,922 | 12,053,242 | |
| Colorado | D | R+4.7 | 1,081,188 | 980,668 | 2,107,472 | |
| Connecticut | D | D+10.4 | 945,347 | 457,749 | 1,424,726 | |
| Florida | R | R+5.0 | 3,590,201 | 3,672,864 | 7,429,707 | |
| Georgia | R | R+16.6 | 1,287,690 | 1,864,202 | 3,220,943 | |
| Hawaii | D | D+8.7 | 313,629 | 87,172 | 415,347 | |
| Iowa | R | R+0.7 | 412,365 | 1,038,175 | 1,478,753 | |
| Idaho | R | R+38.1 | 0 | 499,796 | 499,796 | |
| Illinois | D | D+10.3 | 3,597,456 | 1,390,690 | 5,138,563 | |
| Indiana | D | R+20.7 | 1,496,976 | 903,913 | 2,428,233 | |
| Kansas | R | R+25.4 | 310,337 | 780,863 | 1,129,022 | |
| Kentucky | R | R+19.9 | 850,855 | 873,507 | 1,724,362 | |
| Louisiana | R | R+14.5 | 877,482 | 943,014 | 1,848,056 | |
| Maryland | D | D+13.0 | 1,504,691 | 783,055 | 2,321,571 | |
| Missouri | R | R+7.2 | 1,158,261 | 1,518,089 | 2,706,402 | |
| North Carolina | R | R+12.4 | 1,632,527 | 1,791,450 | 3,471,720 | |
| North Dakota | D | R+27.4 | 212,143 | 98,553 | 310,696 | |
| New Hampshire | R | D+1.4 | 221,549 | 434,847 | 656,396 | |
| Nevada | D | R+2.6 | 494,805 | 284,640 | 810,068 | |
| New York | D | D+18.3 | 4,384,907 | 1,625,069 | 6,702,875 | |
| Ohio | R | R+2.1 | 1,961,171 | 3,464,356 | 5,425,527 | |
| Oklahoma | R | R+31.1 | 596,750 | 763,433 | 1,446,846 | |
| Oregon | D | D+4.2 | 1,128,728 | 565,254 | 1,780,550 | |
| Pennsylvania | R | D+2.5 | 2,334,126 | 2,925,080 | 5,558,525 | |
| South Carolina | R | R+17.1 | 704,384 | 857,167 | 1,595,935 | |
| South Dakota | R | R+21.3 | 193,340 | 197,848 | 391,188 | |
| Utah | R | R+45.5 | 258,955 | 626,640 | 902,884 | |
| Vermont | D | D+20.1 | 216,972 | 75,398 | 307,034 | |
| Washington | D | D+7.2 | 1,549,708 | 1,204,584 | 2,818,651 | |
| Wisconsin | D | D+0.4 | 1,632,697 | 1,301,183 | 2,948,909 |
Source. MIT Election Data + Science Lab — 2004 US Senate returns, party-classified by literal ballot party · statewide certified totals. Real returns — nothing estimated.