FRESNO, Calif. (AP) – When school officials announce the name of the Fresno High School prom king on Saturday, Cinthia Covarrubias will be wearing a tuxedo just like the six boys vying for the honor.

School officials this week added the 17-year-old’s name to the ballot for prom king, reversing a previous district protocol that allowed only males to run for king and females for prom queen.

Gay youth advocates called it a landmark victory for campus gender expression and said they believe it’s the first time in the U.S. that an openly transgender student has run for prom royalty.

Covarrubias, who wears black-and-white Vans, baggy shorts and close-cropped brown hair, sometimes identifies herself as Tony. Her date, a close female friend, plans to wear a black dress and red corsage to the prom at an outdoor reception hall surrounded by man-made waterfalls.

“I would never have run for anything if I had to wear a dress,” Covarrubias said.

She considers herself transgender, an umbrella term that covers all people whose outward appearance and internal identity don’t match their gender at birth.

“My freshman year I just started feeling different,” she said. “When I decided to change to be like this, all of a sudden I said, ‘Wow, I feel OK. I feel like finally I’m being me.'”

She has no current plans, however, to permanently alter her gender through hormones or surgery.

A native of Jalisco, Mexico, Covarrubias said she has bucked rigid expectations of how a girl in her culture should behave. Explaining the meaning of terms like “queer” and “transgender” to her parents and eight siblings has at times been painful, she said.

Covarrubias said she was honored her classmates nominated her for prom king last Friday, but administrators quickly dampened her enthusiasm by saying she could only run for queen.

Tiffani Sanchez, a science teacher who advises the school’s Gay-Straight Alliance, complained.

“Cinthia is still really learning who she is,” she said. “We want her to know that there’s a safe space for her here and we support her.”

On Wednesday, school officials shifted course, saying the district’s lawyers had recommended adding Covarrubias’ name to the ballot to comply with a state law protecting students’ ability to express their gender identity on campus.

“We always want to do the right thing by our students,” Vice Principal Sheila Uriarte said. “This is why we came to this decision.”

The law, passed in 2000, requires schools to protect students from discrimination on the basis of their sexuality, gender or “gender expression.”

Gay and lesbian advocates say that means creating a comfortable environment for students like Covarrubias to cross-dress.

“It’s really important for an individual student like Cinthia to be able to feel she has the same access to participate in this rite of passage,” said Carolyn Laub, director of the Gay-Straight Alliance Network. “We are growing as a society to accept much more diversity in gender expression, and that’s a positive thing.”

Some students criticized the decision to put Covarrubias on the ballot.

“I like lesbians, but they shouldn’t be allowed to run for king,” said senior Erich Logan, 18, as he stood outside the stately high school building.

But Leanne Reyes, 16, said Covarrubias had her vote.

“It’s not like the stereotype where the king has to be a jock and he’s there with the cheerleaders anymore,” said Reyes, a senior. “We live in a generation now where dudes are chicks and chicks are dudes.”

Covarrubias is giddily looking forward to the prom, but acknowledged being a little nervous.

“I’m happy I actually made a difference about changing the law and the policy so you can run for your choice,” Covarrubias said.