2018 New York State Senate election

The vote totals for each party were:

Party	Votes	Percentage	Swing
Democratic	3,242,586	55.98%	4.48%
Republican	1,926,123	33.25%	3.27%
Conservative	253,452	4.38%	0.69%
Independence	155,542	2.69%	0.38%
Working Families	143,776	2.48%	0.40%
Women's Equality	33,835	0.58%	0.11%
Reform	25,362	0.44%	0.12%
Green	10,539	0.18%	0.36%
Stop de Blasio	415	0.01%	New
Upstate Jobs	347	0.01%	New
Tax Revolt	278	0.00%	0.02%

Sources:^[2][10][11]

Five incumbent Republican senators did not seek re-election in 2018. They were:

• Thomas Croci (R), District 3^[12]
• William J. Larkin Jr. (R), District 39^[13]
• John Bonacic (R), District 42^[14]
• Kathy Marchione (R), District 43^[15]
• John A. DeFrancisco (R), District 50^[16]

Seven incumbent senators (all Democrats) ran for re-election, but were defeated in the September 13 primaries.^[17] They were:

• Tony Avella (D-District 11)
• Jose Peralta (D-District 13)
• Martin Malave Dilan (D-District 18)^[18]
• Jesse Hamilton (D-District 20)
• Marisol Alcantara (D-District 31)
• Jeffrey D. Klein (D-District 34)
• David Valesky (D-District 53)

With the exception of Sen. Dilan, all seven had been members of the Independent Democratic Conference.^[18][19]

The following Republican incumbents were defeated on Election Day:

• Carl L. Marcellino (R-District 5)
• Kemp Hannon (R-District 6)
• Elaine Phillips (R-District 7)
• Martin Golden (R-District 22)
• Terrence Murphy (R-District 40)

The six Democratic members of the IDC who were defeated in the September primaries (Sens. Avella, Peralta, Hamilton, Alcantara, Klein, and Valesky) were also on the ballot in November on either the Independence Party line, the Women's Equality Party line, or both (Sen. Peralta also received votes on the Reform Party line). None of the six was re-elected.^[11]

• The New York State Board of Elections only publishes results for contested primary elections.

Sources:^[2][20][21]

The 3rd district is located on Long Island and includes Medford, Ronkonkoma, and Sayville. Republican Thomas Croci has represented this district since 2015. Croci did not run for reelection.^[12]

In an unexpected upset, Democratic challenger Kevin Thomas defeated Republican incumbent Kemp Hannon.^[22]

Democrat Todd Kaminsky was first elected in a 2016 special election.^[23]

• Tony Avella, incumbent
• John Liu, former New York City Comptroller

• Jose Peralta, incumbent
• Jessica Ramos, community activist

• Simcha Felder, incumbent
• Blake Morris, attorney

• Martin Malave Dilan, incumbent
• Julia Salazar, political activist

• Jesse Hamilton, incumbent
• Zellnor Myrie, lawyer and former legislative director in New York City Council

Democratic challenger Andrew Gounardes defeated Ross Barkan in the Democratic primary and narrowly defeated Golden in the general election.^[24]

• Ross Barkan, journalist
• Andrew Gounardes, 2012 Democratic nominee for NY-SD22

• Jasmine Robinson, legal secretary
• Diane Savino, incumbent
• Brandon Stradford

• Marisol Alcantara, incumbent
• Robert Jackson, former New York City councilman
• Thomas Leon
• Tirso Santiago Pina

Democrat Luis Sepúlveda has represented this district since winning a special election in April 2018.^[25]

• Alessandra Biaggi, Deputy National Operations Director for Hillary Clinton's 2016 presidential campaign
• Jeffrey D. Klein, incumbent

• Andrea Stewart-Cousins, incumbent
• Virginia Perez

Democrat Shelley Mayer has represented this district since winning a special election in April 2018.^[26]

Democrat David Carlucci, a former member of the Independent Democratic Conference (IDC), was first elected in 2010. Like other former IDC members, Carlucci received a Democratic primary challenge in 2018. After defeating Julie Goldberg in the primary,^[27] Carlucci turned back Republican Scott Vanderhoef in the general election.^[28]

• David Carlucci, incumbent
• Julie Goldberg, school librarian

Republican Sen. William J. Larkin Jr. did not seek re-election.^[13]

Republican John Bonacic, who has represented this district since 1999, did not seek re-election, and was succeeded by Democrat Jen Metzger.^[14]

• Pramilla Malick, 2016 Democratic nominee for NYSD-42
• Jen Metzger, Rosendale town councilwoman

Republican Kathy Marchione, who had represented this district since 2013, did not seek re-election, and was succeeded by fellow Republican Daphne Jordan.^[15]

Republican John DeFrancisco has represented this district since 1993 and did not seek re-election.^[16] As of November 7, 2018, Republican Bob Antonacci led Democrat John Mannion by 2,829 votes and declared victory in the race, although absentee ballots remained to be counted.^[29] On November 21, 2018, elections officials confirmed Antonacci's victory.^[30]

• Rachel May, board member of OCRRA and former college professor
• David Valesky, incumbent

• Amanda Kirchgessner, community activist
• Michael Lausell, Schuyler County legislator

• Timothy M. Kennedy (incumbent)
• Shaqurah Zachery, teacher

One question that remained after the 2018 elections was which caucus Democratic senator Simcha Felder would join. Felder, since his first Senate election in 2012, had been a member of the Republican majority.^[31] After the dissolution of the Independent Democratic Conference, Felder remained with the Republicans as the decisive vote for Senate control. Felder maintained throughout his tenure that he would rejoin the Democrats if doing so would benefit his district, but after retaking control of the Senate in the 2018 elections, the Senate Democratic Conference did not allow him to join.^[32] Felder was allowed into the Senate Democratic Conference in July 2019; this action gave the Conference a total of 40 members.^[33][34]