Springfield, the home town of television's favourite dysfunctional nuclear family "The Simpsons", is about to become the gay capital of animated America.

The same-sex marriage debate has been heating up the Canadian parliament, but the hit television show will also take on the controversial issue in Sunday's episode -- a move that has some U.S. Christian Conservatives upset.

As the mayor of Springfield says in a clip of the episode: "Springfield: a place where everyone can marry — even dudes."

"I think television is becoming obsessed with homosexuality. In fact I wouldn't put it past people to dig up reruns of Happy Days and have the Fonz come out as gay," said Robert Knight of Concerned Women for America.

In the show, Springfield will legalize gay marriage to bring in tourists and Homer Simpson will become an ordained minister over the Internet so that he can marry same-sex couples.

And like any tourist initiative, there is a catchy song -- this time, to the tune of Harry Belafonte's Banana Boat.

The song goes: "Gay-o, it's OK-o/Tie the knot and spend all your dough."

"We don't really take any positions for or against anything, we just like to examine all sides of an issue and I think that anyone who would get their political wisdom from a cartoon might be sadly mistaken," "The Simpsons" Executive Producer Al Jean said.

But lots of fans watch for that very reason -- they like the tongue-in-cheek political commentary, sometimes subtle, sometimes blatant.

And there are religious messages as well, making it harder for right-wing critics to criticize the animated show.

Mark Pinsky, author of "The Gospel According to The Simpsons" told ABC News that there are "Too many intelligent, discerning Christians and evangelicals who've adopted the show, who like the show. I think it would be too dangerous quite frankly, and too marginalizing for other leaders of the Christian right to attack the show".

The big mystery that will finally be revealed on Sunday episode is which character will come out of the closet -- but producers aren't talking.

This hasn't kept fans from speculating though.

Nuclear boss Mr. Burns' assistant is a likely candidate, and Scottish groundskeeper Willy a less likely one. But Marge's sister Patty is getting the best odds on one U.S. internet betting site.

With a report from CTV's Kathy Tomlinson