ANNAPOLIS - When Margaret Tossey bought her Honda Civic Hybrid in June 2003, she unknowingly joined a growing revolution.

All the 60-something Ocean Pines art teacher knew was that she wanted a smaller car and that she wanted to play her part in saving the environment.

But as spiking gas prices threaten to pierce drivers' purses this summer, Tossey has found herself among a growing number of car owners finding financial relief in alternative-fuel -- mostly gas-electric hybrid -- vehicles.

U.S. hybrid vehicle sales have increased annually by 88.6 percent since 2000 and are expected to keep climbing, according to figures from R.L. Polk & Co., automotive industry analysts. The trend reflects spiraling gas costs, increasing environmental awareness and a growing array of hybrid-electric vehicles.

"I think it's a great indication of the direction in which customers are moving," said Gigi Kellett, Maryland Public Interest Group spokeswoman. "We're seeing a move towards making an investment in a car that will do more for the environment and the pocketbook."

Nationwide registration for hybrid vehicles rose to 43,435 in 2003, a 25.8 increase from 2002, according to Polk. Maryland recorded 1,851 purchases, ranking it fifth in registrations behind California, Virginia, Florida and Washington state.

In Maryland, 3,129 hybrids and 132 electric cars are among the 4,521,891 vehicles registered statewide, said Motor Vehicle Administration spokesman Jeff Tosi.

That figure is expected to increase to more than 13,793 vehicles by 2009, according to the Maryland Department of Legislative Services.

Demand for hybrid-electric cars across the region has been "unbelievable," said Chris Sommer, Toyota Prius salesman at Jim Coleman Toyota dealership in Bethesda. "When they first came out,(demand) was a little slow at first until everyone understood they didn't have to plug them in," unlike all-electric vehicles.

"They've been flying out of here," said Annapolis Honda dealer Michael Alesandrini of the Honda Insight and Honda Civic Hybrid. "We sell them all day every day."

"You tend to see more interest in purchasing fuel-efficient vehicles when gas prices go up," said the Maryland Energy Administration's Mike Li, and there is a three-month wait time for those vehicles throughout the state.

Gas costs have already reached an all-time high, and according to American Automobile Association Mid-Atlantic spokeswoman Sue Akey, they will likely continue to climb. Prices range from $1.76 per gallon for regular gas to $1.92 per gallon for premium, a 12 percent increase over last year.

Hybrid-electrics are powered by a combustion engine and an electric motor. The motor is driven by a battery, which absorbs energy usually wasted during braking, coasting and idling. Some hybrids, like the Honda Insight, automatically shut off when the vehicle stops, thus saving energy and yielding better mileage.

Of the three hybrids now available, Honda Civic Hybrid, Honda Insight and Toyota Prius, the five-speed manual Insight offers the best mileage -- 60 miles per gallon in the city and 66 mpg on the highway.

Tossey, who drives about 30 miles from her home to work at Parkside High School in Salisbury, said her hybrid vehicle is a blessing.

"I'm very happy with its performance," she said. "(Now) I stop at the gas station once a week instead of four to five times a week."

Tossey said it took her a while to get comfortable with her smaller vehicle after driving a Ford Ranger pickup. Once bigger hybrid vehicles become available, demand should increase, she said.

"It's hard for Americans to purchase small vehicles," she said.

Several car manufacturers plan to cater to that particular American taste by launching hybrid trucks and SUVs in the next few years.

Ford's hybrid Escape will be available this summer, General Motors plans to offer hybrid versions of the Chevy Silverado and GMC later this year, and Lexus and Toyota hybrid SUVs will be available in 2005.

"We already have people making deposits on the (Toyota Highlander Hybrid)," said Sommer.

To sweeten the pot, several states offer or plan to offer financial incentives for purchases of alternative-fuel vehicles.

The Internal Revenue Service offers tax deductions of up to $2,000 for hybrid-electric vehicles and $4,000 for electric vehicles, which will phase out by 2006.

Since 2000, Maryland has offered a 5 percent sales tax exemption of up to $2,000 for electric vehicles and $1,500 for hybrid-electric vehicles, which will expire July 1.

The incentive was created "to promote market transformation for new vehicles technologies," said Li. "If we can get more people to buy (fuel-efficient vehicles) the auto companies will build more and the price will go down."

The average cost of a hybrid is about $20,700.

Maryland Delegate Jon S. Cardin, D-Baltimore County, unsuccessfully tried to extend the incentive during the 2004 General Assembly session.

The U.S. market has been "held hostage by foreign oil companies," said Cardin. "The best way to reduce our dependence on foreign oil is to use less of it."

But other lawmakers said the estimated $2.7 million price tag for extending the program was too high for a tight budget, though Cardin said costs would be recouped.

"For every $1 you put into this program, you make $4 or $5," said Cardin, who raved about his Honda Insight. "I thought it was a win-win."

Encouraging Marylanders to buy hybrids and electric vehicles is also sound environmental policy, argued Cardin.

Maryland ranks among states with the highest air pollution. Baltimore and 13 of the state's 23 counties appear on a list of 474 counties, in 31 states, failing to meet stricter ozone standards, according to the Environmental Protection Agency.

Vehicle emissions will account for about 30 percent of volatile organic compounds and 50 percent of nitrogen oxides in the Baltimore-Washington corridor in 2005, said Donna Heron, spokeswoman for EPA's Mid-Atlantic Region. These two gases react with other compounds to form ozone or smog, which is harmful to human health and more prevalent in the summer.

Though there isn't enough information to determine the exact impact of the increasing number of hybrid and electric vehicles on air quality, environmentalists are encouraged by the trend.

Dru Schmidt-Perkins, executive director of 1000 Friends of Maryland said, "I get very excited when I see them on the road."