The high spirits of the Alvin Ailey dancers were contagious at the company’s gala Wednesday, a post-performance supper at the Sheraton Hotel for 1,300 guests that raised $2.7 million. Once the dancers arrived, the dance floor filled up with a happy mix of amateurs and professionals, and many more who couldn’t fit were swaying on the perimeters. For a longtime board member, Patricia Laskawy, the mood had one definitive source. “The real halo is Alvin,” Ms. Laskawy said of the dancer and choreographer who founded the company in 1958. “He was a remarkable human being and the dancers reflect that. His heart, grace, and soul is palpable.” One newcomer to the gala was S. Epatha Merkerson, who plays Lieutenant Anita Van Buren on the television show “Law & Order.” As honorary chairwoman of the dance theater, Ms. Merkerson introduced, on the City Center stage, the company premiere of Twyla Tharp’s “The Golden Section.” She arrived at the gala wearing a dress designed by a friend, Emilio Sosa. “This is an extremely pride-filled moment,” Ms. Merkerson said. Her first encounter with the dance company happened when her mother took her to a performance in her hometown of Detroit as a surprise on her 16th birthday. “That was 38 years ago,” Ms. Merkerson said, noting that her 54th birthday was on Tuesday. There was much to celebrate at the party, including a sleep-away camp reunion for Robert Gersten — the counselor and father of Alvin Ailey’s executive director, Sharon Gersten Luckman — and art collector Charles Diker. They both attended the Brant Lake Camp in the Adirondacks as young men.