Ford's Fusion and Buick's Lucerne are proving to be hot sellers among the wealth of new cars and trucks offered by domestic and foreign automakers this model year.

With Buick's first V-8 in a decade along with an upgraded interior and completely new styling, the Lucerne started off with sales of 285 units in October, 2,724 in November, 5,812 in December and 6,107 last month. The surge has given it a 23.9 percent market share for the full-size sedan market, which includes Ford's Five Hundred and Crown Victoria, the Mercury Montego and Grand Marquis, and the LeSabre, one of two models it replaced.

Meanwhile, Ford's intermediate-size Fusion sold 9,999 units in January, more than double October's total, giving it a 5.08 percent share of the hotly contested midsize premium market that includes the Toyota Camry, Honda Accord and Chevrolet Impala, the perennial sales leader in the segment.

"Ford has had a gap for a long time between its Focus and its Five Hundred," said Tom Libby, senior director, industry analysis at JD Power & Associates, which compiles monthly sales figures. "Now ... it's apparently hit the sweet spot. It also helps that the Fusion has gotten extremely positive reviews in the automotive press."

Interestingly, the Mercury Milan, which is almost identical to the Fusion with the exception of some cosmetics and an upgraded interior, is not experiencing the same strong sales. Its sales reached 2,023 in January, a slight drop from December's 2,111 units and not all that much higher than sales of 1,336 in October, when it was introduced.

Pontiac is another big winner for General Motors, thanks to almost sell-out status for its Solstice sports roadster, strong sales of its new Torrent midsize SUV and increasingly robust sales of the G6. Pontiac's sales hit 37,545 in January, up 55 percent from a year ago.

"What's happened is that Pontiac had several new products hitting the market simultaneously" Mr. Libby said. "Pontiac has momentum now and is countering the voices of doom."

Toyota also has had a strong sales performance, with a 14 percent increase in sales in January from a year ago. It was helped by a slew of new products including the new Camry, Yaris and the FJ Cruiser, as well as the new Lexus ES350 and LS460. "Toyota does not let up," Mr. Libby said.

On the down side, sales of Jeep's Commander plunged last month, as did another Daimler/Chrysler entry, the Mercedes R Class. Mr. Libby said it was too early to say if there was a trend since it usually takes four months to gauge how well a new product is doing.