These days, it’s obvious: The pop culture universe belongs to “Glee.”

Fox’s gay-friendly hit TV series, which returns Tuesday for its “back nine” episodes of the season, has sold more than 4 million downloaded songs on iTunes and sparked a national tour, earning both a Peabody and Golden Globe award.

Oprah Winfrey gave the Queen of All Media’s stamp of approval Wednesday, welcoming the cast with a real show choir.

And showbiz notables from Madonna to Neil Patrick Harris will be featured in upcoming episodes, drenching poignant coming-of-age stories about a group of high school show choir outcasts in a deluge of Broadway tunes, campy attitudes and gay icons. It’s a potent stew for an army of fans known as Gleeks (“Glee” + geek) fired up by show tunes, adolescent angst and snappy, pop culture-savvy dialogue.

“For the most part, the show is about a very specific idea, which is that when you are this age in high school your life is a fantasy,” said creator and executive producer Ryan Murphy, a former show choir member who came out at 15 and has woven those experiences into “Glee.” “When you walk down the hall, you feel like you’re in the spotlight.”

As enthusiasm builds for “Glee,” the hubbub feels suspiciously like the buzz surrounding a show that once held the same place in the pop culture zeitgeist: the ABC dramedy “Ugly Betty.”

In 2007, when “Betty” was hot, the awards and accolades flowed, including 18 Emmy nominations and star America Ferrera making Time magazine’s list of 100 most influential people.

Now, a day after “Glee” returns to the air, “Ugly Betty” will broadcast its last episode, undone after four seasons by falling ratings and a decided lack of excitement. The series, once a forward-looking showcase for gay characters and gay culture, concludes as “Glee” hits a new apex.

For those who track gay culture on TV, a baton has been passed, pushing gay-friendly TV even further into the mainstream.

“There is definitely a changing of the guard,” said Marc Leonard, senior vice president of multi-platform programming for the gay-centered cable channel Logo. “I always saw ‘Ugly Betty’ as a bridge to a modern take on gay characters and gay media. ‘Glee’ is heading further into that postmodern direction … an integrated existence (where) being gay is not such a big deal.”

Leaving ‘Planet Gay’

Leonard described early gay-friendly TV shows as existing on “Planet Gay,” putting characters in a bubble almost exclusively centered on gay culture.

“Glee” expands that focus, featuring a proud, openly gay student in Chris Colfer’s Kurt Hummel, a fondness for show tunes and a flamboyant take on surviving as an outsider.

It builds a series where even the heterosexual characters are negotiating themes that resonate with the gay audience.

This is a mix that “Ugly Betty” also pioneered, featuring Ferrera’s thick-spectacled, braces-wearing Betty Suarez struggling at beauty-obsessed Mode magazine while gay characters (and one transgender person) negotiated typical relationship issues.

Packaged like a glitzy, fashion-fueled soap opera, “Ugly Betty” merged Latino, gay and geek cultures into a percolating tale of an underdog’s struggle.

“That underdog theme is something the gay community understands well,” Leonard said.