The 2018 Senate elections were held on November 6, 2018 to elect class 1 Senators to the Senate. Those elected would serve a six-year term from January 3, 2019-January 3, 2025.
After the 2010 Democrats thought they would lose their majority in 2012 since they had 23 seats to defend while the Republicans only had 10. They won many races in this class' previous elections in 2000 and 2006. Along with President Obama's re-election the Democrats pulled off stunning victories across the country defending all of their incumbents, only losing one open seat and gaining three additional seats.
However the math stands against them again. They will have 24 Democrats and 1 Independent who caucuses with them to defend against just 8 seats for the Republicans. They will also be defending seats in red states like Indiana, Missouri, Montana, North Dakota and West Virginia in addition to seats in perennial purple states like Florida, Michigan, Ohio, Pennsylvania, Virginia and Wisconsin.
4 Democratic women and 4 Republican women were elected or re-elected bringing the total number of women from 21 (16D and 5R) to 29 (20D to 9R).
Only 2 Democrats lost their seats, Indiana's Joe Donnelly and Missouri's Claire McCaskill both of whom won in 2012 because their opponents' campaigns imploded. North Dakota has a tendency to vote for a personality regardless of party affiliation, thus Heidi Heitkamp's re-election.
Republican gain Republican hold Democratic gain Democratic hold Independent gain Independent hold
|Arizona||Jeff Flake||Republican|| Incumbent lost re-election,
|Kyrsten Sinema (Democratic)|
|California||Dianne Feinstein||Democratic|| Incumbent re-elected,
|Jeff Denham (Republican)|
|Connecticut||Chris Murphy||Democratic|| Incumbent re-elected,
|Lawrence F. Cafero (Republican)|
|Delaware||Tom Carper||Democratic||Incumbent retired, Democratic hold||
Lisa Blunt Rochester (Democrat) Michael Ramone (Republican)
|Florida||Bill Nelson||Democratic||Incumbent retired, Democratic hold||
David Jolly (Republican)
Val Demings (Democrat)
Carlos Beruff (Independent)
|Hawaii||Mazie Hirono||Democratic|| Incumbent re-elected,
Kymberly Pine (Republican)
|Indiana||Joe Donnelly||Democratic|| Incumbent lost re-election,
|Susan Brooks (Republican)|
|Maine||Angus King||Independent|| Incumbent re-elected,
| Paul LePage (Republican)|
John Baldacci (Democrat)
|Maryland||Ben Cardin||Democratic||Incumbent re-elected, Democratic hold||
Andy Harris (Republican)
|Massachusetts||Elizabeth Warren||Democratic|| Incumbent re-elected,
|Kerry Healey (Republican)|
|Michigan||Debbie Stabenow||Democratic|| Incumbent re-elected,
|Justin Amash (Republican)|
|Minnesota||Amy Klobuchar||Democratic-Farmer-Labor|| Incumbent re-elected,
|Chris Dahlberg (Republican)|
|Mississippi||Roger Wicker||Republican|| Incumbent re-elected,
|Jim Hood (Democratic)|
|Missouri||Claire McCaskill||Democratic|| Incumbent lost re-election,
|Ann Wagner (Republican)|
|Montana||Jon Tester||Democratic|| Incumbent re-elected,
|Dennie Rehberg (Republican)|
|Nebraska||Deb Fischer||Republican|| Incumbent re-elected,
|Brad Ashford (Democratic)|
|Nevada||Dean Heller||Republican|| Incumbent lost re-election,
|Jackie Rosen (Democratic)|
|New Jersey||Bob Menendez||Democratic||Incumbent retired, Democratic hold.|| M. Teresa Ruiz (Democratic)|
Kim Guadagno (Republican)
|New Mexico||Martin Heinrich||Democratic|| Incumbent re-elected,
|Dianna Duran (Republican)|
|New York||Kirsten Gillibrand||Democratic|| Incumbent re-elected,
|Tom Reed (Republican)|
|North Dakota||Heidi Heitkamp||Democratic|| Incumbent re-elected,
|Kevin Cramer (Republican)|
|Ohio||Sherrod Brown||Democratic|| Incumbent re-elected,
|Josh Mandel (Republican)|
|Pennsylvania||Bob Casey, Jr.||Democratic|| Incumbent re-elected,
|Pat Meehan (Republican)|
|Rhode Island||Sheldon Whitehouse||Democratic|| Incumbent re-elected,
|Donald Carcieri (Republican)|
|Tennessee||Bob Corker||Republican|| Incumbent re-elected,
|Jim Cooper (Democratic)|
|Texas||Ted Cruz||Republican|| Incumbent lost re-nomination,
| Rick Perry (Republican)
Ted Cruz (Tea Party)
Beto O'Rourke (Democratic)
|Utah||Orrin Hatch||Republican||Incumbent retired, Republican hold|| Mia Love (Republican)|
Scott Howell (Democrat)
|Vermont||Bernie Sanders||Democrat||Incumbent re-elected, Democratic hold||Phil Scott (Republican)|
|Virginia||Tim Kaine||Democratic|| Incumbent re-elected,
|Ken Cuccinelli (Republican)|
|Washington||Maria Cantwell||Democratic|| Incumbent re-elected,
|David Reichert (Republican)|
|West Virginia||Joe Manchin||Democratic|| Incumbent re-elected,
|Evan Jenkins (Republican)|
|Wisconsin||Tammy Baldwin||Democratic||Incumbent lost re-elected, Republican gain.||Scott Walker (Republican|
|Wyoming||John Barrasso||Republican||Incumbent retired, Republican hold|| Dave Freudenthal (Democratic)|
Liz Cheney (Republican)
Race Break Down
- Jeff Flake was elected in 2012 by a close margin considering Arizona's Republican tilt. In 2016 fellow Republican Senator John McCain was re-elected to a 7th term by a large margin but Donald Trump only won by 5%. Flake was challenged by Kelli Ward who pulled him to the right while Democratic Rep. Kysten Simena was able to sneak by due to backlash to President Trump's policies.
- Dianne Feinstein won re-election in 2012 to her fourth full term by a large margin winning the most votes any senate candidate has ever won. Her leadership on the Judiciary Committee put her in the spotlight as she led the Democrats through several Supreme Court Nominee Hearings. There was significant talk about her retirement but she decided to run again. She won by a closer margin (58% instead of 62.5%) than before but only because there was lower turnout.
- Chris Murphy won election in 2012. He is a leader on gun safety which is extremely popular in his home state. He was never in any danger. He was re-elected by a large margin.
- Tom Carper retired in 2018 after three terms representing Delware in the Senate. Lisa Blunt Rochester won the Senate election only two years after winning the open congressional seat representing Delaware. She became the first woman to represent Delaware and the first African American to represent Delaware in the Senate.
- Bill Nelson retired in 2018 after three terms representing Florida in the Senate. The open threw both sides into a frenzy. Each side had intense primaries with big names such as Charlie Christ, Rick Scott, Pam Bondi and Alan Grayson throwing their names into the ring. In the end David Jolly, who lost his seat in 2016, was the Republican Nominee and Val Demings, who won her Congressional seat in 2016, was the Democratic Nominee. Carlos Beruff ran as an indepedent pealing votes away from Jolly allowing Demings to win. Demings is the first woman and the first African American to represent Florida in the Senate. Demings was also helped by the Democratic Gubernatorial nominee Gwen Graham's surprise win.
- Mazie Hirono was elected in 2012. After winning 63% of the vote against a popular former governor, Hirono had no issue winning re-election. She was the most popular Hawaiian politician at the time of her re-election.
- Joe Donnelly was elected in 2012 with 50% of the vote against an extremely flawed candidate in a fluke election. Although he was one of the most moderate members of the Democratic Caucus and the backlash against President Trump's policies it did not help him in the end. He lost an very close race in a recount against Republican Rep. Susan Brooks by only a few thousand votes. Susan Brooks became the first woman to represent Indiana in the Senate.
- Angus King was elected in 2012 as an Independent. His popularity in the state has never fallen below the 50% mark and he is only second in popularity to fellow Senator Susan Collins. He was easily re-elected.
- Ben Cardin sailed to re-election in 2012 and repeated the feat in 2018.
- Elizabeth Warren won a very close election in 2012 against a very popular Republican but was in no danger in 2018 because of the state's heavy Democratic Lean. The only person who could have made it a real race would have been Republican Governor Charlie Baker who ran a successful campaign for re-election.
- Debbie Stabenow was re-elected to a third term in 2012. Although President Trump won Michigan by the slimmest margin, a few thousand votes, 2016, Stabenow was never really in danger. The mix of two things caused Stabenow's to be more interesting: backlash against Trump's policies and the state trending away from Democrats at the state level. She defeated Republican Rep. Justin Amash by a moderate margin.
- Amy Klobuchar won re-election in 2012 with over 70% of the vote. Fellow Minnesotan Al Franken won re-election in the Republican wave year 53% to 42%. Klobuchar's largest hurdle was the question whether she would serve a full term if she were to run for President. She was easily re-elected.
- Roger Wicker was elected in 2008 to a serve the remainder of a term then won his first full term in 2012. He won re-election by a large margin.
- Claire McCaskill won election in 2006 with less than 50% of the vote in a Democratic wave year. In 2012 she won against the now definition of a flawed candidate: Todd Akin. (See: 'Legitimate Rape'). In 2000 Missouri was considered a swing state however it has trended Republican. In 2008 it went Republican by a few thousand votes. In 2012 it went to Republicans by 10%. In 2016 it went Republican by 16%.
- McCaskill ran what was considered one of the best campaigns. Even though there was National backlash against President Trump it was not enough to save McCaskill who lost to Republican Rep. Ann Wagner.
- Jon Tester has won election and re-election to this Senate seat with 49% amd 48.5%. He ran against Republican Former Rep. Dennie Rehberg who represented all of Montana as the Representative-at-large. This was a hard fought battle however Tester survived from running what was considered one of the best campaigns, second only to Heidi Heitkamp, while Rehberg ran a low energy campaign.
- Deb Fischer won in 2012 against former Democratic Governor and former Democratic Senator Bob Kerrey. Former Rep. Brad Ashford ran a spirited campaign but could not overcome the state's Republican lean and the popularity of Fischer. The interesting part of the campaign was the crossover endorsement from Nebraska's other Republican Senator Ben Sasse, who claimed Fischer was too conservative and catered too much toward President Trump.
- Dean Heller narrowly won election in 2012 against a candidate with several ethics investigations pending against them. In 2016, Democrat Catherine Cortez Masto won election to the Senate in a very good year for Republicans beating a very strong Republican Candidate, Joe Heck who ran for Nevada's Governor's seat successfully in 2018.
- Heller was the top target for Senate Democrats who had few other places to look for seats to pick up. Rep Jackie Rosen decided to run for the Senate seat at the prompting of Former Senator Reid.
- Rosen won the seat by 1%. Heller had been dragged down by President Trump while Rosen was seen as too politically motivated and self-interested. Rosen became the second woman elected to the Senate and along with Cortez Masto became the fifth pair of women to represent a state in the Senate. (California starting in 1992, Maine in 1996, Washington in 2000, and New Hampshire in 2010.)
- Bob Menedez won re-election to a second full term in 2012. However, he was scandal plagued starting in 2014. He was striped of his committee chairmanship in 2014 and was indicted in 2017. This caused a large headache for Democrats. Several other state leaders destroyed each other's credibility to run. Stephen Sweeney and Steve Fulop ran each other into the ground while Ruiz ran a positive campaign. Former Lt. Governor Kim Guadagno was the Republican Nominee but was dragged down by her ties to impeached Former Governor Chris Christie. Ruiz became the first woman to represent New Jersey in the Senate.
- Martin Heinrich was easily elected in 2012 and easily won re-election in 2018. The main question was whether he would run for President in 2020 and finish out his term.
- Kirsten Gillibrand was easily elected to a full in 2012 with over 70%. The main question was whether she would run for President in 2020 and finish out his term. She was re-elected easily in 2018.
- In 2012 Heidi Heitkamp was considered a longshot to win in Ruby red North Dakota. Many pundits had predicted the seat would go to a Republican. However, Heitkamp pulled off a razor thin victory by about 3000 votes and surprised everyone. Heitkamp was moderately popular in the conservative state despite her political affiliation.
- Republicans convinced Republican Rep. Kevin Cramer to run against Heitkamp. Despite the state's voting for Republican Presidental Nominee 63% to 27% in 2016 and Sen. John Hoeven winning re-election 78% to 17% in 2016 Heitkamp pulled off a second upset to win re-election. It is important to remember North Dakota has a long history of sending Democrats to the Senate.
- Sherrod Brown won re-election in this swing state easily in 2012. Brown has a large following within the state and easily beat his 2012 challenger, Josh Mandel, again.
- Democrat Bob Casey is an institution in Pennsylvania. Despite the state re-electing Pat Toomey in 2016 and voting for Donald Trump in the same year it has a slight lean toward the Democrats. Casey won re-election by an expectedly close margin.
- Democrat Sheldon Whitehouse was re-elected without issue in 2012. He was re-elected easily in 2018.
- Republican Bob Corker was re-elected by a large margin in 2012 and was re-elected in 2018.
- In 2016 Republican Ted Cruz was a vocal opponent of Donald Trump and got a surprise primary challenger in Former Republican Governor Rick Perry. Cruz was considered too conservative even for Texas. The result was Perry winning the nomination but Ted Cruz was unsatisified and ran on the Tea Party line. This caused the Republican vote to be split and Democrat Beto O'Rourke to win in a surprise victory.
- In 2012 Republican Orrin Hatch declared he would not run for re-election however he briefly changed his mind and started to run for re-election. He was convinced to drop out upon seeing he would lose in the primary. Republican Rep. Mia Love ran for the nomination and won. She then easily won the seat and became the first woman to represent the state of Utah in the Senate and the first Republican Woman of color in the Senate.
- Independent-turned-Democrat Bernie Sanders won over 90% in the Presidential Primary in 2016. He easily won re-election in 2018.
- Democrat Tim Kaine's popularity in Virginia helped Hillary Clinton carry the state in 2016 and helped him win his first re-election in 2018.
- Democrat Maria Cantwell easily won re-election in 2012 and then again in 2018.
- Democrat Joe Manchin easily won election to his first full term in 2012 despite Mitt Romney winning the state by double digits. In 2014 in elected its first Republican Senator in a generation. In 2016 it went for Republican Donald Trump by double digits but elected a Democrat to the Governor's Mansion at the same time. Manchin was considered the most conservative Democrat in the Senate for most of his first eight years.
- Despite a hiccup due to his daughter's involvement with the Epipen controversy Manchin won re-election.
- Democrat Tammy Baldwin narrowly won her seat in 2012 while Obama won re-election and Governor Scott Walker survived a recall election. In 2016 Republicans Ron Johnson and Donald Trump won in the state. Baldwin ran against a tough challenger. The two swapped leads in the polls all summer but in the fall Baldwin opened up a consistent but single point lead. She won re-election in part because of the backlash against Donald Trump and Scott Walker.
- Republican John Barrasso retired in 2018. Republican Congresswoman-at-large Liz Cheney won the open seat easily.