With High Gas Prices, Buyers Shift Their Focus Downward The Toyota Prius C, with a combined E.P.A. fuel-economy rating of 50 miles per gallon, is in such demand that a dealer in Florida reportedly levied a $7,000 premium on the $19,710 vehicle, a scaled-down version of the class-leading hybrid. Toyota, which began sales of the C on March 12, moved more units in its first three days than either Chevrolet, with its plug-in-hybrid Volt, or Nissan, with its purely electric Leaf, managed in all of February. The C's runaway popularity might be credited to rising gasoline prices and Toyota's improved quality and dependability. But analysts also identify a broader tendency among American consumers to move down market into smaller segments when they encounter sticker shock at the pump: from sport utility vehicles to crossovers; midsize to compact sedans; compact to subcompact hatchbacks. Recent sales seem to bear both theories out. "Cars and crossovers, our most fuel-efficient vehicles, are now two thirds of our business," Jim Cain, a spokesman for General Motors, said in an interview. "The Sonic is doing fantastically well after a few months on the market," he added, referring to the new compact hatchback and sedan. The brand sold 7,900 Sonics last month, its best month. The Ford Focus, with 23,350 in sales, turned in its best February since 2000. Erich Merkle, a Ford sales analyst, said in an interview that the automaker was commanding its highest share of the small-car market in nearly a decade. Shoppers can find any number of roomy midsize cars promising 30 highway m.p.g. or better, and as G.M. and Ford have shown, the midsize segment is booming, too. "I absolutely think those results are a huge response to high gas prices," Lacey Plache, chief economist at Edmunds.com, said in an interview. Historically, people's interest in compacts and hybrids just ratchets right up when fuel prices rise. The whole Prius line has had trouble keeping up with demand. Mr. Merkle of Ford would not speculate on what gas prices would have to reach for consumers to move more quickly into smaller cars. "My best answer is that I don't know," he said. Still, many industry analysts say any price increase at the pump would have to be sustained to be meaningful. "The small car results are a good sign of the acceptance of those vehicles, but if you're asking me if their sales will reach the magnitude of midsized cars, I'd say it's not likely soon," Christopher Hopson, a sales forecaster at IHS Automotive, said. The sweet spot in the United States is midsize. Small cars are also benefiting from high gas prices amid relatively optimistic economic indicators. He cautioned that the balance could be upset at any time. Really high gas prices would hit the economy as a whole, and the last thing we'd worry about at that point is small car sales.