To the dismay of traditionalists, the holiday season seems to shift earlier every year, with retailers selling Christmas decorations well before Halloween. But this year, the season will get a legitimate jump-start of sorts—at least for millions of American Jews.

In other words, make way for Thanksgivukkah.

In a rare convergence of the calendar, Thanksgiving and the first day of Hanukkah, the eight-day Jewish festival of lights that typically commences close to Christmas, fall on the same date in 2013: Nov. 28. And Thanksgivukkah has become a bold platform for expression, with creations ranging from sweet-potato latkes to the “Menurkey.”

The reason for the fuss: It is a holiday mash-up that has happened only once before—in 1888—according to those who track the Jewish calendar. And it is one that isn’t set to happen again for potentially another 70,000-plus years.

Meet the maker of the ‘Menurkey’

While Hanukkah, which commemorates a Jewish military victory over Greek forces in the second century B.C. and the miracle of a day’s worth of lamp oil lasting for eight, is technically a minor holiday on the Jewish calendar, it has become increasingly prominent in the past century as part of the broader seasonal push.

A few see commercial opportunities in Thanksgivukkah, as well. Dana Gitell, a community specialist with Boston-based elder-care provider Hebrew SeniorLife, has started a Thanksgivukkah Facebook page and is promoting a line of Thanksgivukkah commemorative items, including a T-shirt done in a Woodstock rock-festival motif with the catchphrase “8 Days of Light, Liberty and Latkes.” (Latkes are the potato pancakes typically served throughout Hanukkah.)

Not to be outdone is Asher Weintraub, a 9-year-old New Yorker who has created what he dubs the Menurkey—a menorah, the candelabrum that is the centerpiece of the holiday, in the shape of a turkey. With help from his filmmaker parents, Asher funded his project with a successful $25,000 campaign on the fundraising website Kickstarter over the summer (it netted $48,345). The family is now hoping to sell as many as 2,500 in versions both ceramic (for $150) and plaster ($50).

The Weintraubs are also expanding on the concept in other ways, from a Menurkey iPhone app to a Menurkey theme song. Sample lyric: “Thanksgiving and Hanukkah, come light the Menurkey. Once in a lifetime, the candles meet the turkey.”

Part of what’s driving the Thanksgivukkah fervor is that Hanukkah is a holiday “with room for creativity,” says Jennie Rivlin Roberts, founder of ModernTribe.com, an online store that specializes in contemporary Jewish items. Roberts own contribution? A game called No Limit Texas Dreidel that she started marketing in 2007—it is a modern take on the holiday pastime of spinning the dreidel, a kind of Hanukkah-themed top.

And that isn’t factoring in other pop-culture-inspired Hanukkah high jinks. In that sense, Thanksgivukkah picks up where comedian Adam Sandler’s “Hanukkah Song” or a viral “Hanukkah Hey Ya!” video (using music from the song by the hip-hop group Outkast) left off.

Synagogues and other Jewish organizations are also joining in the Thanksgivukkah chorus. In Boston, Combined Jewish Philanthropies, a local fundraising group, has created a website, ThanksgivukkahBoston.com, to promote the holiday and suggest ways to celebrate it (one example: making Hanukkah-themed corn-husk dolls). As project director Jeff Levy explains, the occasion is too significant to go unheeded. “This is like the new millennium,” he says.

At Temple Beth Sholom in Santa Ana, Calif., synagogue member Hollis O’Brien, a caterer, is leading a Thanksgivukkah cooking class at the end of October, replete with recipe tips for such hybridized holiday dishes as sweet-potato latkes and a Jewish-style brisket with a cranberry glaze. And since doughnuts are also popular at Hanukkah as part of the holiday’s emphasis on oil and fried foods, O’Brien has plans to showcase them as well. “Usually, I fill them with strawberry jelly, but this year I’m going to use pumpkin cream,” she says.

Speaking of culinary crossovers, the BuzzFeed website recently suggested an entire Thanksgivukkah menu. The highlight: a purple-hued turkey, brined in Manischewitz Concord Grape wine.

The reason the hybrid holiday is such a rarity owes to the nature of the Jewish calendar, which is partly influenced by the lunar cycle and doesn’t correspond on a consistent basis with the Gregorian or Christian calendar.

Making matters more confusing is the fact that Thanksgiving’s place on the calendar has also moved since the federal recognition of the holiday by President Abraham Lincoln in 1863. For many years, it was observed on the final Thursday of November, as opposed to its present incarnation on the fourth Thursday.

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Some Novembers have five Thursdays—the push to codify the fourth Thursday came during President Franklin D. Roosevelt’s administration as a way to guarantee a longer shopping season. (A few states continued to celebrate on the final Thursday.)

Researchers say that makes 1888 the lone previous Thanksgivukkah on a national scale, notwithstanding the fact that Thanksgiving and Hanukkah have crisscrossed during other days of Hanukkah’s eight-day run in select years. For example, in 1899, Thanksgiving fell on the fourth day of Hanukkah.

Not everyone sees the point to Thanksgivukkah or any sort of modern reinterpretation of Hanukkah: Traditionalists argue that it turns the holiday into something it’s not. “It’s really pathetic that to sell Judaism to the next generation it has to be made into a gimmick,” says Binyamin L. Jolkovsky, publisher of JewishWorldReview.com.

That is hardly the only issue facing Thanksgivukkah boosters. It isn’t exactly something that can be parlayed into an ongoing celebration: The next Thanksgivukkah isn’t slated until 79043, according to researchers.

Which is OK by Gitell, who holds trademarks on the term “Thanksgivukkah.” “Part of what makes it so exciting is its once-in-an-eon uniqueness,” she says.

Eli Lansey, a New York-based physicist who has studied the calendar convergence, couldn’t agree more. “If ever there was a year for deep-fried turkey, this is it,” he says.

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