According to a Tony rule, there must be at least seven eligible actors in order for a category to have a maximum of five nominees. That rule states, "There shall be no more than four nominees in each category; provided, that if there are at least seven eligible candidates for nomination in a Best Performance category, then there shall be five nominees in that category; and provided, further, that the Tony Awards Administration Committee shall also have the sole discretion to reduce the number of nominees to fewer than four (or five), but, in no event, fewer than two, in a particular category for the current season or to delegate this discretion to the Nominating Committee."
Those eligible for nomination in the Best Performance by an Actress in a Leading Role in a Musical category follow:
Janet Dacal - Wonderland
Sutton Foster - Anything Goes
Beth Leavel - Baby It's You!
Patina Miller - Sister Act
Donna Murphy - The People in the Picture
Sherie Rene Scott - Women on the Verge of a Nervous Breakdown