Running Jan. 1, 2015, at 7 PM through Jan. 4 at 7 AM, the variety show will feature up to 100 Metropolitan Room artists.

The centerpiece of the marathon – Jan. 2-3 at 7 PM — will be Marilyn Maye, who will offer her fourth annual By Request holiday party-show, coming right after she rings out 2014 with back-to-back shows on New Year’s Eve. She will be joined by pianist/conductor Billy Stritch, bassist Tom Hubbard and drummer Ray Marchica.

“Having Marilyn smack in the middle of this three-day variety show signals that this marathon is much more than an endurance test,” said Bernie Furshpan, the Metropolitan Room’s managing partner, in a statement. “We are going to celebrate the range of shows at the Metropolitan Room and program the best and most original… it’s this impressive mix that makes our club truly one of a kind.”

The marathon will also feature comedians, magicians, novelty performers and masters of ceremony. Complimentary breakfast will be served on Saturday and Sunday mornings.

Customers who attend the longest — either for unbroken stretches of time or for combined attendance recorded over three days by the club’s reservationists — will win special prizes and be entered in the official record of the event. (Sleeping will not be permitted in the showroom.) Day passes cost $25 per person or $60 for a three-day pass. The club offers a complimentary beverage with each ticket purchased. There will be no food or beverage minimums throughout the marathon, except for Marilyn Maye, whose By Request requires a separate ticket purchase ($35 plus a two-drink minimum).

For reservations call (212) 206-0440 or visit www.metropolitanroom.com. The Metropolitan Room is located at 34 West 22nd Street.