Tom Jones, shown here in early 2005, is back at the MGM with a set that balances his sex-machine image with grown-up singing. Photo by Jeff Scheid.

Wayne Newton and the Scintas are doing Christmas shows this weekend. But Tom Jones seemed a little confused last Saturday when someone threw a Santa Claus doll onstage instead of the usual female undergarments.

All he wants for Christmas is the only thing he ever wanted:

"Just want to be your play thing, don't need to be your smokin' gun," he wailed in a blues shout, accompanied by rudimentary guitar picking and minimalist drum beat.

"Don't want you holdin' out for me, I just want to have a little fun," he proclaimed from his perch on a stool, knees strategically spread wide to advertise whatever might be for sale.

"Let the truth be told, I only want to get me some."

Uh-huh.

Let the other singers worry about the silver bells and the silent nights, and let the 66-year-old sex machine keep the home fires stoked. Waiting a full hour to take his coat off was perhaps the Tomcat's nod to holiday decorum in this stint at the MGM Grand -- an unusually late-in-the-year one -- that continues through Wednesday.

But if the truth really be told, the ageless singer figured out long ago how to pull his perennial Las Vegas show into a near-perfect balance.

The lascivious fun of that obscure blues song -- Earl Thomas' "Git Me Some" -- was immediately followed by a serious take on the blues, Bill Withers' "Grandma's Hands," showing off a voice that's still as tuned and powerful as it was 20 years ago.

"The Voice," in fact, had a hard time not oversinging "what we refer to as 'standards,' " a trio of classics he didn't sound too fired-up about introducing, as though he was doing them because Rod Stewart did.

"Here's That Rainy Day" suggested Sinatra country is not where Jones' brand of nuance lies. But he lightened up for a bossa nova "Fly Me to the Moon." And by the time he got to "That Old Black Magic," he was up to his old tricks again, with bulging eyes and an extra lusty, deep-throated punch on "Only your kiss can put out the fire!"

Van Morrison's "Cry for Home" and Jerry Lee Lewis' "End of the Road" showcased the "mature Tom," an era marked by looser clothing and a kind of lion-in-winter respectability the singer enjoys in Great Britain, but not necessarily on these shores.

That image permits fun indulgences that occasionally take off as hit singles in Europe: "Sex Bomb," or "Resurrection Shuffle," a lesser-known tune from the past that's been dusted off for a techno-sounding relaunch (a la Elvis Presley's "A Little Less Conversation").

They're mixed in with the classics, such as "She's A Lady," "Delilah" and "It's Not Unusual," which take the singer back to an earlier era of Las Vegas, even as they're updated with modern arrangements and a hot four-piece horn section.

It all adds up to a Las Vegas tradition that may not involve eggnog and mistletoe, but is every bit as hard for the ladies to resist.