The union representing thousands of doormen, porters and other New York City building workers is preparing for a possible strike vote if talks with building owners break down.

Local 32BJ of the Service Employees International Union is planning a rally and strike authorization vote on Wednesday.

The contract for 30,000 apartment building workers expires on April 20.

Elected officials including City Council Speaker Melissa Mark-Viverito and City Comptroller Scott Stringer will join labor leaders for a rally before the vote.

The strike authorization vote would allow Local 32BJ’s bargaining committee to call a strike if negotiations with the Realty Advisory Board break down.

The union says its members deserve a raise that keeps pace with the cost of living.

The realty board did not immediately return an email seeking comment.

(AP)