CHICAGO – The popularity of hybrids still continues to increase, despite their cost, according to new survey, and Portland is among one of the “greenest” cities when it comes to driving.

KGW photo

A car buyer looks over a hybrid Toyota Prius at Broadway Toyota.

The Cars.com survey showed that 59% of shoppers have purchased or would consider purchasing a hybrid as their next vehicle.

The survey also asked questions to help it rank which cities in the United States are the most environmentally friendly, when it comes to driving. Both Portland and Seattle ranked in the top 5.

 Rankings: See entire list of cities

"Gas prices definitely play a role in hybrid interest, because West Coast cities traditionally have higher gas prices on average than the rest of the country," said Cars.com editor in chief Patrick Olsen. "The Cars.com Green Index also shows that interest is high in markets that are traditionally concerned with environmental issues."

San Francisco earned the highest “green” ranking in the study, with Portland as No. 2 followed by Seattle. Sacramento and San Diego finished out the top 5.