She had been diagnosed with ALS late last year.
Luker graced both the stage and the screen, though she was most recognized for her memorable Broadway roles.
She began her three-decade-long Broadway career as an understudy for the role of Christine Daaé in “The Phantom of the Opera” from 1988 to 1991. Throughout the 1990s, she played parts in “The Secret Garden,” “Show Boat” and “The Sound of Music.”
Luker earned her first of three Tony nominations in 1995 for portraying Magnolia in “Show Boat.” Her later works in “The Music Man” (2000) and “Mary Poppins” (2007) would eventually lead to her second and third nods.
As the 2000s wore on, Luker continued to perform on Broadway, but began to take on film and television roles as well. Starting with her gig in the 2000 TV movie “Cupid & Cate,” the actor went on to appear in “The Good Wife,” “Law & Order: Special Victims Unit” and “NCIS: New Orleans.” She played Michele Downey in “Bull” this year in her final acting role.
The star had her last stage performance in Kennedy Center’s 2019 production of “Footloose,” in which she played a small-town minister’s narrow-minded wife. By this time she had also appeared in three feature films, including 2014’s “The Rewrite.”
In June, Luker hosted a virtual benefit for ALS called “At Home With Rebecca Luker.” She sang during the prerecorded concert, raising funds and awareness for the disease.
Luker is survived by her husband, actor Danny Burstein; brother Roger; sister Suzanne; mother Martha Hales; and stepfather Lamar Hales.