The 2018 United States Senate election in Wisconsin took place on November 6, 2018, to elect a member of the U.S. Senate from Wisconsin. This election coincided with a gubernatorial election, U.S. House elections and various other state and local elections. Incumbent Democratic senator Tammy Baldwin won re-election to a second term, defeating Republican nominee Leah Vukmir by more than 10 percentage points. This was one of ten Democratic-held Senate seats up for election in a state Donald Trump won in the 2016 presidential election. The primary elections were held on August 14, with a filing deadline on June 1. Baldwin was unopposed for the Democratic nomination, while Vukmir defeated Charles Barman, Griffin Jones, George Lucia and Kevin Nicholson in the Republican primary.
Democratic primary Candidates Nominee Tammy Baldwin, incumbent U.S. senator
Endorsements
Results
Republican primary Candidates Nominee Leah Vukmir, state senator and State Senate Assistant Majority Leader
Eliminated in primary Charles Barman Griffin Jones George Lucia Kevin Nicholson, businessman and member of the Wisconsin Board of Veterans Affairs
Declined David Clarke, former Milwaukee County sheriff Sean Duffy, U.S. representative (running for reelection) Scott Fitzgerald, State Senate Majority Leader Mike Gallagher, U.S. representative Glenn Grothman, U.S. representative Eric Hovde, businessman and candidate for the U.S. Senate in 2012 Rebecca Kleefisch, lieutenant governor of Wisconsin Dale Kooyenga, state representative Nicole Schneider, businesswoman Duey Stroebel, state senator Charlie Sykes, talk radio host Scott Walker, governor of Wisconsin (running for reelection)
Endorsements
Polling Poll source Date(s)administered Samplesize Marginof error KevinNicholson LeahVukmir Other UndecidedEmerson CollegeEmerson College July 26–28, 2018 238 ± 6.5% 35% 35% 3% 27%Marist CollegeMarist College July 15–19, 2018 355 ± 6.1% 38% 28% <1% 34%Hodas & Associates (R)Hodas & Associates (R) July 12–16, 2018 600 ± 3.0% 33% 20% – 47%Marquette UniversityMarquette University July 11–15, 2018 266 ± 7.0% 32% 34% 2% 30%Marquette University June 13–17, 2018 274 ± 6.9% 37% 32% 1% 30%Hodas & Associates (R) June 7–12, 2018 600 ± 3.0% 28% 14% – 58%The Tarrance Group (R)The Tarrance Group (R) May 31 – June 4, 2018 800 ± 3.5% 29% 36% – 35%American Viewpoint (R)American Viewpoint (R) May 29–31, 2018 500 ± 4.4% 32% 30% – –Hodas & Associates (R) April 30 – May 3, 2018 240 ± 6.0% 46% 15% – –WPA Intelligence (R) April 2–4, 2018 1,028 ± 3.1% 45% 27% – 28%Marquette University February 25 – March 1, 2018 243 ± 8.2% 28% 19% 2% 49%WPA Intelligence (R) January 22–23, 2018 350 ± 5.2% 48% 9% 1% 42%WPA Intelligence (R) January 2–3, 2018 350 ± 5.2% 27% 10% 2% 60%WPA Intelligence (R) December 6–7, 2017 1,004 ± 3.1% 30% 23% 2% 45%
Poll source Date(s)administered Samplesize Marginof error DavidClarke SeanDuffy UndecidedMagellan Strategies (R)Magellan Strategies (R) February 15–16, 2017 300 ± 5.7% 32% 26% 42%
Results
General election Endorsements
Debates Complete video of debate, October 8, 2018 Complete video of debate, October 13, 2018
Predictions SourceRankingAs ofThe Cook Political Report October 26, 2018Inside Elections November 1, 2018Sabato's Crystal Ball November 5, 2018Fox News November 5, 2018CNN November 5, 2018RealClearPolitics November 5, 2018
Polling
Poll source Date(s)administered Samplesize Marginof error TammyBaldwin (D) LeahVukmir (R) Other UndecidedResearch Co. November 1–3, 2018 450 ± 4.6% 50% 39% – 11%Emerson College October 29–31, 2018 604 ± 4.1% 53% 44% – 3%Marquette University October 24–28, 2018 1,154 LV ± 3.2% 54% 43% – 1% 1,400 RV ± 3.0% 52% 42% – 3%Ipsos October 12–18, 2018 1,193 ± 3.0% 54% 39% 3% 5%Public Policy Polling (D) October 10–11, 2018 816 ± 3.4% 52% 42% – 6%Marquette University October 3–7, 2018 799 LV ± 3.9% 53% 43% – 2% 1,000 RV ± 3.6% 53% 42% – 3%Marist College September 30 – October 3, 2018 571 LV ± 4.8% 54% 40% 1% 5% 781 RV ± 4.1% 53% 40% 1% 6%Ipsos September 14–24, 2018 1,109 ± 3.0% 52% 39% 4% 5%Marquette University September 12–16, 2018 614 LV ± 4.4% 53% 42% – 2% 800 RV ± 4.0% 52% 40% – 4%Suffolk UniversitySuffolk University August 18–24, 2018 500 ± 4.4% 50% 42% – 8%Marquette University August 15–19, 2018 601 LV ± 4.5% 49% 47% – 2% 800 RV ± 4.0% 51% 43% – 4%Emerson College July 26–28, 2018 632 ± 4.2% 50% 36% 4% 10%Marist College July 15–19, 2018 906 ± 3.8% 55% 38% 1% 6%SurveyMonkey/Axios June 11 – July 2, 2018 968 ± 4.5% 56% 40% – 4%Marquette University June 13–17, 2018 800 ± 4.0% 49% 40% – 8%Public Policy Polling (D) March 15–16, 2018 910 ± 3.3% 51% 39% – 10%
with Kevin Nicholson Poll source Date(s)administered Samplesize Marginof error TammyBaldwin (D) KevinNicholson (R) Other UndecidedEmerson College July 26–28, 2018 632 ± 4.2% 49% 40% 3% 9%Marist College July 15–19, 2018 906 ± 3.8% 54% 39% 1% 6%SurveyMonkey/Axios June 11 – July 2, 2018 968 ± 4.5% 55% 42% – 3%Marquette University June 13–17, 2018 800 ± 4.0% 50% 39% – 7%Public Policy Polling (D) March 15–16, 2018 910 ± 3.3% 51% 38% – 11%
with generic Republican Poll source Date(s)administered Samplesize Marginof error TammyBaldwin (D) GenericRepublican UndecidedSurveyMonkey/AxiosSurveyMonkey/Axios February 12 – March 5, 2018 1,668 ± 3.6% 49% 46% 5%
with David Clarke Poll source Date(s)administered Samplesize Marginof error TammyBaldwin (D) DavidClarke (R) Other UndecidedMagellan Strategies (R) February 9–10, 2017 500 ± 4.4% 49% 35% 2% 14%
with Sean Duffy Poll source Date(s)administered Samplesize Marginof error TammyBaldwin (D) SeanDuffy (R) Other UndecidedMagellan Strategies (R) February 9–10, 2017 500 ± 4.4% 49% 36% 2% 13%
Results Despite initial expectations of a potentially close race, Baldwin ended up winning by over 10 percentage points, which was the highest margin of victory for a Wisconsin Democratic statewide candidate in 2018. She ran up the margins in the traditional Democratic strongholds of Milwaukee and Madison, but also won in western Wisconsin, Green Bay and most of the counties bordering Illinois, including Racine, Rock, and Kenosha counties. This was the largest margin of victory for the Democrats in a major Wisconsin statewide campaign (presidential, senate, gubernatorial) since 2008.
By county County Tammy BaldwinDemocratic Leah VukmirRepublican Write-ins Margin Total votes cast # % # % # % # % Adams 4,537 48.3% 4,854 51.6% 8 0.1% -317 -3.3% 9,399 Ashland 4,533 65.8% 2,351 34.1% 8 0.1% 2,182 31.7% 6,892 Barron 8,571 46.3% 9,911 53.6% 11 0.1% -1,340 -7.3% 18,493 Bayfield 5,541 63.1% 3,233 36.8% 1 0.0% 2,308 26.3% 8,775 Brown 59,132 51.4% 55,750 48.5% 184 0.2% 3,382 2.9% 115,066 Buffalo 2,945 49.8% 2,968 50.2% 4 0.1% -23 -0.4% 5,917 Burnett 3,239 43.0% 4,289 57.0% 0 0.0% -1,050 -14.0% 7,528 Calumet 10,741 45.6% 12,822 54.4% 0 0.0% -2,081 -8.8% 23,563 Chippewa 13,798 49.9% 13,830 50.1% 1 0.0% -32 -0.2% 27,629 Clark 5,084 43.7% 6,558 56.3% 2 0.0% -1,474 -12.6% 11,644 Columbia 15,230 56.5% 11,674 43.3% 36 0.1% 3,556 13.2% 26,940 Crawford 3,852 58.8% 2,703 41.2% 0 0.0% 1,149 17.6% 6,555 Dane 228,050 77.6% 65,515 22.3% 414 0.1% 162,535 55.3% 293,979 Dodge 16,007 42.7% 21,482 57.3% 1 0.0% -5,475 -14.6% 37,490 Door 9,442 55.7% 7,494 44.2% 11 0.1% 1,948 11.5% 16,947 Douglas 11,689 62.8% 6,925 37.2% 8 0.0% 4,764 25.6% 18,622 Dunn 9,743 53.0% 8,623 46.9% 1 0.0% 1,120 6.1% 18,367 Eau Claire 29,614 60.9% 18,957 39.0% 71 0.1% 10,657 21.9% 48,642 Florence 729 33.6% 1,438 66.4% 0 0.0% -709 -32.8% 2,167 Fond du Lac 19,065 42.7% 25,496 57.2% 41 0.1% -6,431 -14.5% 44,602 Forest 1,879 47.6% 2,062 52.3% 3 0.1% -183 -4.7% 3,944 Grant 10,554 54.3% 8,860 45.6% 6 0.0% 1,694 8.7% 19,420 Green 10,294 60.4% 6,732 39.5% 11 0.1% 3,562 20.9% 17,037 Green Lake 3,222 39.7% 4,893 60.3% 2 0.0% -1,671 -20.6% 8,117 Iowa 7,270 65.4% 3,835 34.5% 9 0.1% 3,435 30.9% 11,114 Iron 1,459 47.6% 1,605 52.4% 0 0.0% -146 -4.8% 3,064 Jackson 4,370 54.8% 3,611 45.2% 0 0.0% 759 9.6% 7,981 Jefferson 18,055 47.6% 19,809 52.3% 47 0.1% -1,754 -4.7% 37,911 Juneau 4,658 46.1% 5,429 53.8% 9 0.1% -771 -7.7% 10,096 Kenosha 38,296 56.7% 29,181 43.2% 112 0.2% 9,115 13.5% 67,589 Kewaunee 4,287 45.3% 5,158 54.6% 9 0.1% -871 -9.3% 9,454 La Crosse 35,731 62.8% 21,160 37.2% 0 0.0% 14,571 25.6% 56,891 Lafayette 3,592 55.3% 2,900 44.7% 1 0.0% 692 10.6% 6,493 Langlade 3,889 42.6% 5,239 57.4% 0 0.0% -1,350 -14.8% 9,128 Lincoln 6,463 48.3% 6,901 51.6% 15 0.1% -438 -3.3% 13,379 Manitowoc 16,541 46.8% 18,795 53.1% 37 0.1% -2,254 -6.3% 35,373 Marathon 29,084 47.1% 32,661 52.8% 68 0.1% -3,577 -5.7% 61,813 Marinette 7,520 43.6% 9,731 56.4% 1 0.0% -2,211 -12.8% 17,252 Marquette 3,337 46.8% 3,791 53.1% 6 0.1% -454 -6.3% 7,134 Menominee 896 80.3% 220 19.7% 0 0.0% 676 60.6% 1,116 Milwaukee 280,426 71.4% 111,684 28.4% 748 0.2% 168,742 43.0% 392,858 Monroe 8,151 48.7% 8,559 51.2% 21 0.1% -408 -2.5% 16,731 Oconto 7,042 40.4% 10,392 59.6% 15 0.1% -408 -19.2% 16,731 Oneida 9,338 48.0% 10,112 51.9% 23 0.1% -774 -3.9% 19,473 Outagamie 41,618 50.2% 41,354 49.8% 2 0.0% 264 0.4% 82,974 Ozaukee 21,464 42.1% 29,480 57.8% 66 0.1% -8,016 -15.7% 51,010 Pepin 1,529 49.2% 1,578 50.8% 0 0.0% -49 1.6% 3,107 Pierce 9,216 52.8% 8,247 47.2% 3 0.0% 969 5.6% 17,466 Polk 8,299 44.8% 10,245 55.2% 0 0.0% -1,946 -10.4% 18,544 Portage 20,170 58.1% 14,510 41.8% 45 0.1% 5,660 16.3% 34,725 Price 3,136 47.2% 3,515 52.8% 0 0.0% -379 -5.6% 6,651 Racine 45,397 52.3% 41,213 47.5% 140 0.2% 4,184 4.8% 86,750 Richland 4,000 57.3% 2,980 42.7% 6 0.1% 1,020 14.6% 6,986 Rock 42,616 62.7% 25,322 37.2% 73 0.1% 17,294 25.5% 68,011 Rusk 2,654 43.9% 3,381 55.9% 11 0.2% -727 -12.0% 6,046 St. Croix 18,765 47.1% 21,069 52.9% 30 0.1% -2,304 -5.8% 39,864 Sauk 16,960 58.8% 11,866 41.2% 0 0.0% 5,094 17.6% 28,826 Sawyer 3,938 48.6% 4,159 51.3% 3 0.0% -221 -2.7% 8,100 Shawano 7,414 41.5% 10,438 58.5% 0 0.0% -3,024 -17.0% 17,852 Sheboygan 24,183 45.7% 28,667 54.2% 75 0.1% -4,484 -8.5% 52,925 Taylor 3,028 37.7% 5,005 62.3% 2 0.0% -1,977 -24.6% 8,035 Trempealeau 6,526 53.6% 5,633 46.3% 9 0.1% 893 7.3% 12,168 Vernon 7,495 57.8% 5,459 42.1% 5 0.0% 2,036 15.7% 12,969 Vilas 5,308 42.5% 7,166 57.4% 17 0.1% -1,858 -14.9% 12,491 Walworth 20,299 44.9% 24,844 54.9% 73 0.2% -4,545 -10.0% 45,216 Washburn 3,664 46.6% 4,190 53.3% 4 0.1% -526 -6.7% 7,858 Washington 23,072 32.9% 47,102 67.1% 1 0.0% -24,030 -34.2% 70,175 Waukesha 84,147 38.1% 136,190 61.7% 293 0.1% -52,043 -23.6% 220,630 Waupaca 9,509 42.6% 12,792 57.3% 15 0.1% -3,283 -14.7% 22,316 Waushara 4,434 42.1% 6,106 57.9% 0 0.0% -1,672 -15.8% 10,540 Winnebago 40,185 53.2% 35,282 46.7% 118 0.2% 4,903 6.5% 75,585 Wood 15,992 48.6% 16,899 51.3% 28 0.1% -907 -2.7% 32,919Totals1,472,91455.4%1,184,88544.5%2,9640.1%288,02910.9%2,660,763 Counties that flipped from Democratic to Republican Buffalo (largest city: Mondovi) Forest (largest city: Crandon) Juneau (largest city: Mauston) Lincoln (largest city: Merrill) Pepin (largest city: Durand) Price (largest city: Park Falls) Sawyer (largest city: Hayward) Chippewa (largest city: Chippewa Falls) Wood (largest city: Marshfield)
Counties that flipped from Republican to Democratic Outagamie (largest city: Appleton) Brown (largest city: Green Bay)
By congressional district As a result of partisan gerrymandering, Baldwin only won three out of the state's eight Congressional districts, despite winning the election comfortably by over ten percentage points. DistrictBaldwinVukmirRepresentative49.6%50.3%Bryan Steil73%26%Mark Pocan56%44%Ron Kind79%21%Gwen Moore43%57%Jim Sensenbrenner47%52%Glenn Grothman48%52%Sean Duffy48%51%Mike Gallagher
See also 2018 United States Senate elections 2018 Wisconsin gubernatorial election 2018 Wisconsin elections
Notes
Partisan clients
References
External links Candidates at Vote Smart Candidates at Ballotpedia Campaign finance at FEC Campaign finance at OpenSecrets
Official campaign websites Tammy Baldwin (D) for Senate John Schiess (I) for Senate (write-in) Leah Vukmir (R) for Senate