While Cronin, a Garden City lawyer running for office for the first time, appears to be facing long odds, supporters point out that he is one of just two Senate challengers statewide who had stockpiled more than $100,000 by midsummer.
Republicans countered that Hannon has a huge cash advantage, with nearly $600,000 in his campaign coffers. They dismissed Cronin's chances, noting that Democrats have said for years they are on the verge of knocking out Hannon, but have never succeeded.
Lawrence Levy, executive dean of the National Center for Suburban Studies at Hofstra University, said Cronin, "seems to be running a more spirited campaign than you tend to see by Democratic Senate candidates on Long Island, and he's obviously raised more money. But Kemp Hannon has been there a long time and he's backed by a strong Republican organization that gets the vote out. I think he's in a pretty strong position."
Hannon seems to be taking no chances. His campaign website and Facebook pages show he made frequent appearances in the district in September, attending street fairs, job fairs, Medicare seminars, library-book giveaways, the Central American parade in Hempstead and a youth football kickoff in Farmingdale.
"Sen. Hannon always runs a hard campaign regardless of who he's running against," said Scott Reif, Senate Republican spokesman. "He's always visible in the community and he's always reminding people of the good work he's done in Albany."
Republicans hold a 33-29 advantage in the Senate, the one area of state government the GOP controls. One new district was created under a redistricting plan this year, meaning 63 seats are up for grabs on Election Day.
Hannon's contest is one of eight that Democrats say will determine who controls the chamber. Another is the fight to replace retiring Sen. Owen Johnson (R-West Babylon) in southwestern Suffolk County.
Hannon won with 60 percent of the vote in 2010, which was a big year for Republicans. But in 2008, he squeaked by with a 3,000-vote win. Democrats are hoping that, as in 2008, a big party turnout for the presidential election will help local candidates like Cronin.
Cronin said he's already knocked on thousands of doors in the central Nassau County Senate district. He has campaigned for raising the minimum wage, protecting abortion rights and tightening gun-control laws. He has endorsements from unions representing a local teachers' group, supermarket workers, retail workers and residential building services employees.
Cronin criticizes Hannon and the Republican majority for backing away from their promise to enact nonpartisan redistricting for 2012 and failing to back campaign-finance overhaul proposals.
"One of the key people who created the problems here in Nassau County shouldn't be the one to try to fix it," Cronin said.
Hannon, longtime chairman of the Senate Health Committee, is championing his role in crafting medical legislation, including drug-insurance programs for the elderly, an assisted living program and a new plan to track painkiller prescriptions. A lawyer, Hannon has served as a key Republican negotiator on numerous bills, including the law to allow same-sex marriage -- although he eventually voted against it.
Like other Republicans, he's touting the Senate GOP's partnership with Democratic Gov. Andrew M. Cuomo in keeping state spending flat the past two years, partly rolling back the unpopular Metropolitan Transportation Authority payroll tax and enacting the state's historic property-tax cap law. Hannon's Facebook page features more than 10 photos of him with the governor.