Elections / 2020 · Senate · IA
Iowa — 2020 U.S. Senate election
Akashicstate2020 Senate electionIowa · U.S. SenateErnstR+6.6
How it voted
Share of the 2020 vote
| Joni Ernst (i) ✓Republican | 51.8% | 864,997 |
|---|---|---|
| Theresa GreenfieldDemocrat | 45.2% | 754,859 |
| Rick StewartLibertarian | 2.2% | 36,961 |
2020Senate margin
D+60R+60
99 counties, each filled by 2020 D-vs-R margin. Hover any county for its result.
County-level results (99 counties) — table
| County | Winner | Margin |
|---|---|---|
| ADAIR, IA | Republican | R+38.7 |
| ADAMS, IA | Republican | R+41.9 |
| ALLAMAKEE, IA | Republican | R+25.6 |
| APPANOOSE, IA | Republican | R+35.0 |
| AUDUBON, IA | Republican | R+32.5 |
| BENTON, IA | Republican | R+25.1 |
| BLACK HAWK, IA | Democratic | D+8.7 |
| BOONE, IA | Republican | R+13.2 |
| BREMER, IA | Republican | R+15.8 |
| BUCHANAN, IA | Republican | R+16.6 |
| BUENA VISTA, IA | Republican | R+21.3 |
| BUTLER, IA | Republican | R+35.2 |
| CALHOUN, IA | Republican | R+38.1 |
| CARROLL, IA | Republican | R+32.9 |
| CASS, IA | Republican | R+34.5 |
| CEDAR, IA | Republican | R+15.5 |
| CERRO GORDO, IA | Democratic | D+0.8 |
| CHEROKEE, IA | Republican | R+34.4 |
| CHICKASAW, IA | Republican | R+25.8 |
| CLARKE, IA | Republican | R+30.1 |
| CLAY, IA | Republican | R+32.2 |
| CLAYTON, IA | Republican | R+25.3 |
| CLINTON, IA | Republican | R+6.6 |
| CRAWFORD, IA | Republican | R+29.8 |
| DALLAS, IA | Republican | R+5.9 |
| DAVIS, IA | Republican | R+38.6 |
| DECATUR, IA | Republican | R+34.1 |
| DELAWARE, IA | Republican | R+32.4 |
| DES MOINES, IA | Republican | R+0.9 |
| DICKINSON, IA | Republican | R+30.0 |
| DUBUQUE, IA | Republican | R+1.1 |
| EMMET, IA | Republican | R+27.7 |
| FAYETTE, IA | Republican | R+19.3 |
| FLOYD, IA | Republican | R+8.6 |
| FRANKLIN, IA | Republican | R+32.2 |
| FREMONT, IA | Republican | R+38.5 |
| GREENE, IA | Republican | R+25.6 |
| GRUNDY, IA | Republican | R+38.5 |
| GUTHRIE, IA | Republican | R+33.3 |
| HAMILTON, IA | Republican | R+22.5 |
| HANCOCK, IA | Republican | R+34.9 |
| HARDIN, IA | Republican | R+30.8 |
| HARRISON, IA | Republican | R+31.0 |
| HENRY, IA | Republican | R+24.8 |
| HOWARD, IA | Republican | R+14.3 |
| HUMBOLDT, IA | Republican | R+42.3 |
| IDA, IA | Republican | R+47.0 |
| IOWA, IA | Republican | R+23.4 |
| JACKSON, IA | Republican | R+17.7 |
| JASPER, IA | Republican | R+17.5 |
| JEFFERSON, IA | Democratic | D+6.1 |
| JOHNSON, IA | Democratic | D+40.3 |
| JONES, IA | Republican | R+19.1 |
| KEOKUK, IA | Republican | R+39.9 |
| KOSSUTH, IA | Republican | R+35.1 |
| LEE, IA | Republican | R+6.3 |
| LINN, IA | Democratic | D+12.6 |
| LOUISA, IA | Republican | R+27.7 |
| LUCAS, IA | Republican | R+39.7 |
| LYON, IA | Republican | R+65.9 |
| MADISON, IA | Republican | R+31.7 |
| MAHASKA, IA | Republican | R+43.6 |
| MARION, IA | Republican | R+31.2 |
| MARSHALL, IA | Republican | R+4.9 |
| MILLS, IA | Republican | R+34.4 |
| MITCHELL, IA | Republican | R+18.4 |
| MONONA, IA | Republican | R+34.3 |
| MONROE, IA | Republican | R+39.8 |
| MONTGOMERY, IA | Republican | R+39.9 |
| MUSCATINE, IA | Republican | R+4.4 |
| O'BRIEN, IA | Republican | R+54.1 |
| OSCEOLA, IA | Republican | R+57.3 |
| PAGE, IA | Republican | R+41.5 |
| PALO ALTO, IA | Republican | R+29.1 |
| PLYMOUTH, IA | Republican | R+46.7 |
| POCAHONTAS, IA | Republican | R+43.4 |
| POLK, IA | Democratic | D+14.0 |
| POTTAWATTAMIE, IA | Republican | R+13.8 |
| POWESHIEK, IA | Republican | R+9.8 |
| RINGGOLD, IA | Republican | R+42.3 |
| SAC, IA | Republican | R+44.0 |
| SCOTT, IA | Democratic | D+3.1 |
| SHELBY, IA | Republican | R+37.4 |
| SIOUX, IA | Republican | R+68.6 |
| STORY, IA | Democratic | D+14.8 |
| TAMA, IA | Republican | R+16.8 |
| TAYLOR, IA | Republican | R+49.1 |
| UNION, IA | Republican | R+28.9 |
| VAN BUREN, IA | Republican | R+40.5 |
| WAPELLO, IA | Republican | R+13.8 |
| WARREN, IA | Republican | R+15.6 |
| WASHINGTON, IA | Republican | R+19.3 |
| WAYNE, IA | Republican | R+46.0 |
| WEBSTER, IA | Republican | R+19.0 |
| WINNEBAGO, IA | Republican | R+16.5 |
| WINNESHIEK, IA | Republican | R+3.8 |
| WOODBURY, IA | Republican | R+12.4 |
| WORTH, IA | Republican | R+14.2 |
| WRIGHT, IA | Republican | R+29.5 |
presidential baselinePresident 2020R+8.2Senate 2020R+6.6vs. baselineD+1.6
Iowa's 2020 Senate race ran 1.6 points more Democratic than the presidential race on the same ballot.
Iowa's Senate margins
Every contest in our store, 1978–2022
| Year | Margin (D minus R) |
|---|---|
| 1978 | −3.2% |
| 1980 | −7.9% |
| 1984 | +11.8% |
| 1986 | −32.5% |
| 1990 | +9.1% |
| 1992 | −42.4% |
| 1996 | +5.1% |
| 1998 | −37.9% |
| 2002 | +10.4% |
| 2004 | −42.3% |
| 2008 | +25.4% |
| 2010 | −31.1% |
| 2014 | −8.3% |
| 2016 | −24.5% |
| 2020 | −6.6% |
| 2022 | −12.2% |
Same ballot, 2020IA
Source. MIT Election Data + Science Lab — 2020 US Senate returns, party-classified by literal ballot party · county returns aggregated from precinct-level results. Real returns — nothing estimated.