When a new hybrid Prius is delivered to the Rockingham Toyota Scion dealership in Salem, N.H., it sells almost immediately.
"Every time we get one on the lot, it lasts about five hours," said Marc Smith, the general sales manager. "Most times, it's gone before it even reaches the dealership."
High gas prices and consumers' desire for greener vehicles are driving sales of efficient gas, hybrid and electric cars, dealers and customers said.
In the first four months of 2012, hybrid car sales were up 37.2 percent over last year. Electric car sales were up a staggering 323 percent, but that number is a little deceiving because sales are very low nationally.
That compares to a 13.4 percent hike in other car sales, according to Alan Baum of Baum and Associates, a market research firm.
"Obviously, gas prices are driving the demand," Baum said. "But availability and more options for consumers are also adding to the boom."
Rockingham Toyota Scion sold 13 hybrid cars last month, Smith said.
"The boom kicked in in February as gas prices started to move up," he said. "We could sell a lot more than 13 if we had the cars."
What started as a niche market has expanded to more than 40 different hybrid and electric models.
The Northeast and California continue to be the strongest markets, Baum said.
In Massachusetts, hybrid car registrations accounted for 1.1 percent in 2009 and 2010, according to the state Department of Transportation. In 2011, that number dropped slightly to 6,102 of 697,000 cars, just under 1 percent.
The number of electric cars remains low, but it has more than doubled in the past few years, to 124 cars in 2011.
"Citizens are interested in improving the environment and improving their costs," said Mark Sylvia, commissioner of the Office of Energy and Environmental Affairs. "We're not concerned about a slight decrease because there has been the introduction of electric vehicles. A number of manufacturers identified Massachusetts as a place they want to make their hybrid and electric cars available."