A group of some of the most-employed casting directors in the New York theater industry led a rally in front of Radio City Music Hall Thursday morning as part of an ongoing public effort to secure union contracts for Broadway casting directors.

Bernard Telsey (“Hamilton”), Tara Rubin (“Dear Evan Hansen”), Cindy Tolan (“The Curious Incident of the Dog in the Night-Time”), David Caparelliotis (“A Doll’s House, Part 2”) and Jim Carnahan (“Groundhog Day’) were among a crowd of around 100 people, including actors and members of other unions, who brandished signs that read “I Support Casting Directors” and marched around the midtown block where Radio City is situated.

The rally was timed to coincide with Tony Awards season, when national attention on Broadway is at its peak. The Tony Awards take place Sunday at Radio City; Thursday morning marked the start of load-in and rehearsals for the ceremony.

“We’re really hoping that our rally here today, and the support we have from all the other unions, will elucidate this cause to producers so they understand that we’re serious,” said Rubin, who has cast Broadway shows including Tony contender “Dear Evan Hansen” as well as “Mamma Mia!” and “Billy Elliot.”

Casting directors — who for a dozen years have had union deals with AMPTP for film and TV — are among the only workers on Broadway not to have health care and pension provisions in their deals with producers. For about a year, the group has worked with Teamsters Local 817 to persuade the Broadway League, the trade association of theater producers and presenters, to negotiate a union contract with them.

The League has so far deferred a decision to the National Labor Relations Board, saying in a statement that casting directors are hired as independent contractors and not as employees of a show. “We have had a respectful dialogue in the past year with Teamsters Local 817 but do not believe it would be appropriate for the Broadway League or its producing members to recognize a union as the bargaining representative of professionals who are not employees of our productions,” the statement read.

Casting directors and Local 817 have pushed back, launching a social media campaign called #FairnessForCasting that’s seen public support from Broadway actors including Alex Brightman (“School of Rock”) and Katrina Lenk (“Indecent”) as well as Liam Neeson. Supporters have also capitalized on the Broadway season’s record-breaking $1.45 billion in sales to highlight what they call the unfairness of the current situation.

Supporters note that the pool of theatrical casting directors is fairly small, meaning that the proposed union contract would only apply to about forty people. “Now we just have to keep ramping up the pressure, and ramping up the noise, until the Broadway producers come to their senses,” said Tom O’Donnell, the president of Teamsters Local 817. “They have to understand that this isn’t something that we’re going to get let go.”