Singer Judith Hill attends a screening of Twenty Feet from Stardom during the first day of the 18th Annual Nantucket Film Festival on June 26, 2013 in Nantucket, Massachusetts.

Singer Judith Hill attends a screening of Twenty Feet from Stardom during the first day of the 18th Annual Nantucket Film Festival on June 26, 2013 in Nantucket, Massachusetts. (Andrew H. Walker, Getty Images for The Nantucket F)

The spotlight is shining on the backup singers.

Morgan Neville's documentary on the best backup talent in the business — including Darlene Love, Merry Clayton and Lisa Fischer — has connected with audiences in its limited release. 

Crossing the $1-million mark this Fourth of July weekend, "Twenty Feet From Stardom," now screening in 89 theaters, earned an additional $585,982 over the holiday time-frame to put its four-week total at $1.1 million.

The movie, which premiered at the Sundance Film Festival and has generated primarily positive reviews, centers on the women behind such superstars as Bruce Springsteen, Mick Jagger and Stevie Wonder.

L.A. Times film critic Kenneth Turan called the performers in the film "infectious and irresistible," while Bruce Diones of the New Yorker praised the movie as a "spirited, thoughtful look" at the behind-the-scenes artists.

Radius-TWC distributed the film and will expand it into more theaters in the coming weeks.