Democratic challenger Adam Haber, left, and State Sen. Jack Martins...

Democratic challenger Adam Haber, left, and State Sen. Jack Martins (R-Mineola). Credit: James Escher

Two key Long Island State Senate races could determine if Republicans regain complete control of the chamber or if Democrats win a clear majority, which would give them all the levers of power in Albany.

The stakes are high for both sides. The GOP shares majority control with the five-member Independent Democratic Conference as well as a Brooklyn Democrat who said he will sit with whichever party holds the majority.

"Senate Republicans are fighting for their lives, and how well they do on Long Island will go a long way to determining their fate in Albany," said Lawrence Levy, executive dean of the National Center for Suburban Studies at Hofstra University.

In the most competitive Senate race in Nassau County, Democratic businessman Adam Haber is challenging Sen. Jack Martins (R-Mineola) in the 7th District.

Martins, who is seeking a third term, touts his ability to work with Democrats to hold down taxes, increase aid to schools and combat the use of heroin by young people.

Haber, a Roslyn school board member, has pledged to repeal Nassau County's controversial school-zone speed camera program, reform the Common Core curriculum and use his business expertise to find savings in the state budget.

In the 8th District, Republican Michael Venditto and Democrat David Denenberg are listed on the ballot, but Denenberg has dropped out of the race.

The most-watched race in Suffolk County is in the 3rd District, where environmental activist Adrienne Esposito faces Republican Tom Croci, the Islip Town supervisor. State Sen. Lee Zeldin (R-Shirley) is vacating the seat to run for Congress against Rep. Tim Bishop (D-Southampton).

Esposito, who is unaffiliated with a party but is running on the Democratic line, heads the Citizens Campaign for the Environment, a nonprofit group.

She has attacked Croci for raising property taxes by 28 percent as town supervisor in 2013. Esposito also has tried to link Croci to the toxic dumping scandal at Roberto Clemente Park in Brentwood.

Croci, a commander in the U.S. Navy, has said the tax hike was needed to clean up a financial mess left by his Democratic predecessor and that he was deployed in Afghanistan when the dumping occurred.

A Newsday/News 12/Siena College poll published Oct. 3 showed Croci leading Esposito, 56-29 percent. On Oct. 24, the poll showed Martins leading Haber, 52-37.

In Nassau, Democrats also are focusing on the 6th District, where Sen. Kemp Hannon (R-Garden City) faces Democratic challenger Ethan Irwin, an attorney from Levittown.

Irwin, a former U.S. Marine, has said he would end unfunded state mandates, provide veterans with a free education at local community colleges and enact a circuit breaker for people with fixed incomes to cap their property taxes at a percentage of their income.

Hannon, who was first elected to the Senate in 1989, has focused on his experience holding down taxes, promoting job creation and combating the Island's heroin and opioid use.

In the 5th District, which includes parts of Nassau and Suffolk, Sen. Carl Marcellino (R-Syosset) will take on Democrat Bruce Kennedy, the Sea Cliff mayor.

Kennedy originally had planned to run as a Republican against Assemb. Charles Lavine (D-Glen Cove). But the Nassau Conservative Party said it would not support Kennedy because he had presided over a pair of same-sex marriage ceremonies in the village. Kennedy dropped out of the race, switched parties and announced a challenge to Marcellino.

Following are the State Senate races in Nassau and Suffolk counties on Nov. 4:

District 1: Kenneth LaValle (R, C, I) versus Michael Conroy (D)

District 2: John Flanagan (R, C, I) versus Joseph Lombardi (D)

District 3: Thomas Croci (R, C, I) versus Adrienne Esposito (D, WF, GRE, WEP/Women's Equality Party)

District 4: Philip Boyle (R, C, I) versus John Alberts (D)

District 5: Carl Marcellino (R, C, I) versus Bruce Kennedy Jr.(D, WOR) versus Georgina Bowman (LBT)

District 6: Kemp Hannon (R, C, I) versus Ethan Irwin (D, WF)

District 7: Jack Martins (R, C, I) versus Adam Haber (D, WF)

District 8: Michael Venditto (R, C, I, TR/Tax Revolt Party) versus David Denenberg (D, WF, WEP)

District 9: Dean Skelos (R, C, I) versus Patrick Gillespie Jr. (D, WF)

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