Businessman, GOP district leader and ’08 Assembly contender Tony Nunziato is poised to announce a challenge to Democratic Sen. Joe Addabbo, and he has gained the support of several key local leaders who have been at odds in the past, several Queens sources confirm.

Chief among Nunziato’s backers is NYC Councilman Eric Ulrich, who has been floated (by none other than Senate Minority Leader Dean Skelos) as a potential opponent to Addabbo himself.

The GOP has been casting about for a candidate to take on Addabbo since the former Democratic NYC councilman ousted veteran Republican Sen. Serf Maltese in 2008 – a victory that helped the Dems tip the chamber (just barely) into their control.

The RSCC has polled the district and found a number of potential candidates would put up a strong fight against Addabbo, who has riled a key constituency of the Democratic alliance – LGBT advocates – by voting “no” on gay marriage last December.

Others mentioned include Maltese (grudge match! – sadly, he’s not interested) and former NYC Councilman Anthony Como, who is now being pushed by Skelos et al since Ulrich has decided not to run.

Ulrich said he hasn’t yet heard from Como, and time is running out. Petitions are due to start circulating next Tuesday.

Nunziato is expected to announce his campaign early next week.

Queens GOP Chairman Phil Ragusa is also reportedly in Como’s corner, but the chairman’s arch political enemies – the Haggerty brothers – are backing Nunziato, as is former NYC Council Minority Leader Tom Ognibene, sources said.

The Ragusa vs. Ulrich/Haggerty brothers split was also on display during the GOP convention this week.

Ragusa, once a supporter of Suffolk County Executive Steve Levy, was a late add to Myers Mermel’s meager list of supporters, while the Haggertys and Ulrich backed Rick Lazio.