Off Broadway company Second Stage Theater has nabbed the right to buy Broadway’s Helen Hayes Theater.

Org aims to raise $35 million for the purchase and renovation of the house. Price tag of the right to buy was not disclosed.

Second Stage plans to begin producing in the Hayes in 2010. In the meantime, Martin Markinson, who bought the Hayes with the late Donald Tick in 1987, will continue to operate the venue, currently home to tuner “Xanadu.”

If the sale goes according to plan, Second Stage would become the fourth Gotham nonprofit to acquire a permanent Rialto stage.

Manhattan Theater Club owns and operates the Biltmore, Lincoln Center Theater has the Vivian Beaumont, while the Roundabout produces offerings at both the American Airlines and Studio 54 (and hopes to expand to the rebuilt Henry Miller as well).

The nonprofit and commercial realms have intersected with greater frequency in recent years as production costs have spiraled upward.

Still, the move by Second Stage seems likely to provoke grumbling among radition-minded commercial producers, who see the increasing presence of the nonprofits on Broadway as an incursion by orgs who play by different fiscal rules but nonetheless receive the same level of awards attention and press.

Second Stage will continue to maintain programming in its two other spaces, the 296-seat midtown venue and the 108-seat theater on the Upper West Side, the McGinn/Cazale.

Second Stage was founded in 1979 by current a.d. Carole Rothman with the goal of revisiting American plays that did not succeed the first time around. Since then the org has expanded its mission to include the development of new plays and musicals.

Recent Off Broadway offerings include Edward Albee’s “Peter and Jerry” and Sarah Ruhl’s “Eurydice,” while a handful of alums of the theater, including “The 25th Annual Putnam County Spelling Bee” and “Metamorphoses,” went on to Rialto runs.

Seating slightly less than 600, the Helen Hayes is the smallest theater on Broadway. Originally called the Little Theater when it was built in 1912, the house was renamed in the 1980s when the original Helen Hayes Theater, located nearby, was demolished to make way for the Marriott Marquis.

Past occupants of the Hayes include “The Last Night at Ballyhoo,” “Golda’s Balcony” and “Torch Song Trilogy.”