2018 United States Senate election in Wisconsin

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.

Nominee

 * Tammy Baldwin, incumbent U.S. Senator

Results
[[File:2018 WI US Senate D primary.svg|thumb|Results by county: Baldwin

{{legend|#0b1728|Baldwin—100%}}

{{legend|#162d50|Baldwin—≥90%}} ]]

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)

Polling

 * Notes

Results
[[File:2018 WI US Senate GOP primary.svg|thumb|Results by county {{legend|#e27f7f|Vukmir}}

{{legend|#d75d5d|60–70%}}

{{legend|#e27f7f|50–60%}}

{{legend|#ffb2b2|40–50%}} {{legend|#ff9a50|Nicholson}}

{{legend|#ffcca9|30–40%}}

{{legend|#ffb580|40–50%}}

{{legend|#ff9a50|50–60%}}

{{legend|#ee8e50|60–70%}} ]]

Debates

 * Complete video of debate, October 8, 2018
 * Complete video of debate, October 13, 2018

Predictions

 * Notes

Polling

 * with Kevin Nicholson


 * with generic Republican


 * with David Clarke


 * with Sean Duffy

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 is the largest margin of victory for the Democrats in a major Wisconsin statewide campaign (presidential, senate, gubernatorial) since 2008.

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
Despite winning by over 10 percentage points, Baldwin only won 3 out of 8 Congressional districts.