Could Apple have 3 top-selling smartphones in U.S. during holiday season?

By now it's pretty obvious that Apple's new iPhone 4S will be a big hit during the holiday shopping season.

The company announced record sales of its latest smartphone in the few days after its release last month, and even the battery-drain problems an iOS 5 update last week apparently failed to fix probably won't dissuade many shoppers who really want the newest iPhone for themselves or as a gift.

(Also see: Are heavy iPhone 4S pre-orders a 'tribute to Steve'?)

So it's reasonable to expect the iPhone 4S to be the top-selling smartphone in the U.S. during the fourth quarter.

But based on new data from research firm NPD Group, Apple might have a chance to sweep the top three spots in U.S. mobile handset sales in Q4.

NPD reports that the two biggest-selling mobile handsets in the third quarter were the Apple iPhone 4 and runner-up iPhone 3GS. (They were followed, in order, by two Android devices -- the HTC EVO 4G and Motorola Droid 3 -- and the Samsung Intensity II messaging phone.)

While the iPhone 4S indeed has been setting sales records, Apple continues to sell its older iPhone models through wireless carriers. The iPhone 4 is available through AT&T, Verizon and Sprint for $99 (8GB version) and a service contract, while the 3GS (8GB) is being offered by only AT&T, but for free (with a service contract).

And while that's only one carrier, it's a big one. Plus, free will be pretty hard for a lot of people to turn up. Add in the Steve Jobs factor -- his recent death and the success of his biography arguably have added an aura to Apple and its products -- and it's likely AT&T will move a lot of iPhone 3GS devices through December.

Probably not enough to outsell the top-selling Android, but don't be surprised to see three iPhone models in NPD Group's five top-selling mobile handsets for the fourth quarter.