Automakers are preparing to introduce dozens of fully electric cars and plug-in hybrid vehicles over the next three years, and Hyundai, Kia, Mini, Nissan and Audi will display electric models due in the United States this year. It is a gambit based on the idea that many mainstream car owners will rush to make the leap from gasoline.

But to sell all those cars, the manufacturers have to attract a new class of customer.

Mainstream consumers may be harder to win over than the wealthy luxury car buyers, hard-core environmentalists and early adopters who have flocked to buy Model 3s and delivered Tesla’s rapid sales growth. That may be especially true in the middle of the country, because charging stations are more sparse there than on the coasts, where most Tesla models are sold.

Mr. Westerman, for example, said he’d like an electric car with a range of 600 miles — about as far as his Prius takes him on a full tank of gas.

Manufacturers are developing so many electrified models primarily to compete in China and Europe, where government subsidies and stringent environmental laws are spurring sales of zero-emission vehicles, said Mark Wakefield, a managing director at AlixPartners, a consulting firm. The sales pace is less certain in the United States, in part because gasoline remains cheap and the Trump administration has pulled back on emissions regulations.

“In the U.S., you can’t assume you’re going to be selling 100,000 of one model,” Mr. Wakefield said. “You don’t want to dedicate an entire factory to E.V.s” — as Tesla has done.