NEW YORK - A Norman Rockwell painting titled Saying Grace sold at an auction Wednesday for $46 million, a record for the Saturday Evening Post illustrator and for any artwork sold at an American auction, Sotheby's said.

Two people on the telephone bid against each other for nine minutes before the hammer came down, the auction house said. The buyer's identity was not disclosed.

The painting had a presale estimate of $15 million to $20 million. The $46 million price includes a buyer's premium. In 2006, the auction house sold Rockwell's Breaking Home Ties for more than $15 million, then a record.

The previous auction record for an American artwork was set in 1999, when George Bellows' painting Polo Crowd sold at Sotheby's for $27.7 million, the auction house said.

Another Rockwell painting, The Gossips, sold Wednesday for just under $8.5 million; a third, Walking to Church, fetched a little more than $3.2 million.

For nearly two decades, all three had been on loan at the Norman Rockwell Museum in his hometown, Stockbridge, Mass.

Rockwell was paid $3,500 for Saying Grace, which appeared on the cover of the magazine's Thanksgiving issue in 1951 and was voted Post readers' favorite cover in a 1955 poll.

The illustrator spent 47 years at the magazine and produced 321 covers. He died in 1978.

The three paintings, along with four other Rockwell works, were auctioned by the family of Kenneth Stuart, Rockwell's longtime art director at the magazine.

Rockwell Museum director Laurie Norton Moffatt has expressed hope the three paintings will be returned.

"We cared for them like children," she said. ". . . We hope they come back some day. We believe that's where they belong."