“Miracle of Miracles” indeed.

Fierstein has actually been playing Tevye since January. A number of folks wondered then at casting the raspy-voiced, cross-dressing star of “Hairspray” as the earthy, masculine patriarch. But Fierstein has at least one fan. Sheldon Harnick, who wrote “Fiddler’s” lyrics all those years ago, told The New York Times, “Harvey I had grave doubts about and he’s marvelous.”

Now O’Donnell has signed on to play Fierstein’s ball and chain in what The Times called “one of the boldest bits of replacement casting in Broadway history.” The story continued that the pairing of O’Donnell and Fierstein “makes it truly an Only on Broadway moment, where two openly gay and outspoken actors will play husband and wife in a musical all about the breaking of traditions.”

Wonderful. Make that, “To life, to life, l’chaim!”

O’Donnell and Fierstein are both talented, both musical veterans and both as gay as Prada shoes. Both are even gay activists. Now they’re coming together to play spouses, the sort who have been together through feast and famine. Mostly famine. They’ll have to convince audiences they’re heterosexual, the parents of a passel of daughters and agonizing over their children’s desire to choose their own mates. In other words, they gotta act.

No doubt they will, but I keep thinking of the duet Tevye and Golde sing where Tevye asks, “Do you love me?” and she responds with an incredulous, “Do I what?” Now that’ll be not just Tevye’s question to his wife of umpteen years whom he met on his wedding day. It could also be a point where every gay in the audience snickers. We can’t always be grown-ups.

In a news release “Fiddler’s” producers declared the pairing “a match made in musical-theater heaven.” Obviously they’re looking for O’Donnell’s star power to put butts in the seats of the Minskoff Theater. But they just happen to be advancing the gay cause as well by making this match, finding this find, catching this catch.

Certainly gays have played wife and husband before in big productions, but I sure don’t remember two prominent and out actors doing it. This is another milestone reached. For a tradition-bound little village, that Anatevka sees more growth than a Petri dish.

If O’Donnell and Fierstein fare well together, they could unleash a trend. Theatrical producers might start hunting for out pairings to star in other classic musicals. I picture Ellen DeGeneres as Navy nurse Nellie Forbush in “South Pacific.” To play her love interest, the French planter Emile de Becque, I favor Fierstein. Listen, if he can handle “If I Were a Rich Man,” he can handle “Some Enchanted Evening.”

When she’s done with “Fiddler,” O’Donnell could play Fanny Brice in “Funny Girl.” George Michael would be suitably suave as shady-dealing Nick Arnstein. How about Melissa Etheridge tackling “The Sound of Music” as Maria the iffy nun, with Elton John portraying Captain Von Trapp?

Either Joan Jett or k.d. lang would be a convincing Mame, and Judas Priest frontman Rob Halford could play the wealthy Southerner Beauregard Jackson Picket Burnside. The wildest pairing would be Lea DeLaria and Boy George in “Kiss Me, Kate.” They get to decide which of them plays Lilli and which Fred.

It’s creative matchmaking like that that would make “Fiddler’s” Yente proud