There is a theoretical, magic tipping point for adoption of electric vehicles. Once somewhere between 5 and 10 percent of new car sales are all-electric, some researchers say, huge numbers of drivers will follow. They predict that electric car sales will then soar — to 25 percent, 50 percent and eventually to close to 80 percent of new sales. Early adopters who love shiny new technologies will be replaced by mainstream consumers just looking for a good deal.

Last year, the United States finally passed that elusive mark — 5 percent of all new cars sold in the fourth quarter were fully electric. And earlier this year, all-electric vehicles made up about 7 percent of new car sales.

But even as the nation’s EV market appears to be teetering on the edge of an electric takeover, a hesitant American public — and a still-subpar charging infrastructure — could still hold the country back. A Washington Post-University of Maryland poll shows the current limits of U.S. enthusiasm for the new vehicles, with nearly half of adults (46 percent) saying they prefer to own a gas-powered car or truck. That compares with 19 percent who want a full-electric vehicle, 13 percent who want a plug-in hybrid and 22 percent who want a traditional hybrid vehicle.

Most technologies follow what is known as an “S-curve” for adoption: microwaves, smartphones, even gas-powered cars. First, the new technology reaches only a small segment of the population — new adopters and tech geeks. Then, engineers fix bugs, society builds infrastructure for the new technology, and suddenly adoption skyrockets. Usage can rapidly climb from just 5 to 10 percent of the population to up to 80 percent, where it often plateaus.

This has already happened in some countries with EVs. In Norway, for example, fully electric vehicles made up only about 5 percent of sales in 2013. By 2018, they had climbed to 30 percent. Today, more than 80 percent of cars sold in Norway are fully electric.

“That’s the kind of quintessential example” of the tipping point, said Corey Cantor, a senior associate for electric vehicles at BloombergNEF. California, he said, appears to be following a similar trend: About 7 percent of the state’s new car sales were electric vehicles in 2019, and in the first half of this year it’s about 25 percent.

Some countries or regions seem to shift after reaching 5 percent — others take a little longer. “It’s just an observed point between 5 and 10 percent where you start to see strong growth,” Cantor said.

If the pattern holds, the United States should start to see rapid growth in the next few years. And automakers have gone all-in on the transition. As of early 2023, U.S.-based car companies have announced about $173 billion in spending to shift to electric vehicles. Volkswagen, Ford, BMW, General Motors, and many more car companies are all making electric cars. There are more than 40 all-electric models on offer in the United States.

Part of the hesitation to go electric is driven by a partisan divide. Republicans are much more likely to want to stick with gas-powered cars — two-thirds of them say they prefer those vehicles regardless of cost. Democrats, on the other hand, are less attracted to running on gas; a quarter of them prefer gas-powered cars to other vehicles. There’s little partisan gap in ownership however, with 9 percent of Democrats and 8 percent of Republicans saying they own or lease a fully-electric car.

A huge increase in EV adoption is still possible in the next few years, says Stephanie Valdez Streaty, director of mobility research and development at Cox Automotive. But it depends on how quickly charging infrastructure expands across the country and how quickly electric vehicle prices can come down, she said.

The United States has about 57,000 public charging stations in the country, a number that pales in comparison to infrastructure in China, which has rapidly embraced EVs. (China reportedly built 650,000 public chargers just last year.) And while the federal government is doling out money to build more fast chargers — and Tesla is opening up some of its proprietary charging network to other drivers — progress is still slow.

“Consumers want the same experience as driving an ICE vehicle,” Valdez Streaty said, referring to an internal combustion engine, or gas-powered, vehicle. “When I go to charge, I don’t want to have to wait four hours to charge.”

Americans seem aware of public charging’s limitations. According to The Post-UMD poll, 74 percent of Americans think that gas-powered cars are better for driving more than 250 miles — a range at which drivers would have to use public fast charging stations. (Even Secretary of Energy Jennifer Granholm, who recently went on an EV road trip with a reporter from NPR, faced challenges finding places to plug in.) Gas-powered vehicles are also seen as better on purchase cost (66 percent) and convenience of refueling (75 percent) over EVs.

Leslie Jordan, a 63 year-old retired Navy financial management agent who lives in King George, Va., says climate change is real and “we need to do something” about it. But Jordan, who usually votes for Democrats, won’t be turning in the keys to her dream car — a silver 2020 Impala she ordered directly from the factory — for an EV.

“I live in a very rural area and there are no recharging stations that I know of and there’s no public transportation here,” said Jordan, who also owns a GMC Canyon. “I want to be able to fill up my car and I want to go.”

Even if her town added rapid recharging stations, “I think it would be inconvenient.”

One of the largest benefits of driving an electric vehicle — the low cost of charging — is less well known. Just over 4 in 10, 42 percent of Americans think that electric cars are cheaper to charge than gas-powered cars. An analysis by the progressive think tank Energy Innovation found that when charging at home, “filling up” an EV is cheaper than gas in all 50 states; fast charging can occasionally be more expensive than gas in certain areas.

“The whole educational piece is huge,” Valdez Streaty said.

Just over a third of Americans say EVs are better for driving places they go day-to-day than gas-powered vehicles, but majorities say they are better for reducing climate change (59 percent) and air pollution (70 percent).

Other factors could also slow the transition. Supply chain problems could slow production of batteries and EVs themselves; meanwhile, the United Auto Workers have gone on strike, in part over concerns that the electric transition could reduce the overall number of auto industry jobs.

But even those who say that they would never buy an electric vehicle may change their minds in the future, thanks to the steady progress of the innovation S-curve. In 2000, Gallup polled U.S. adults on whether they had, or planned to buy, cellphones. Nearly half of Americans who didn’t own a cellphone said they planned never to buy one.

The poll was conducted by The Post and the University of Maryland’s Center for Democracy and Civic Engagement from July 13 to 23. The sample of 1,404 U.S. adults was drawn from the NORC AmeriSpeak Panel, an ongoing survey panel recruited through random sampling of U.S. households. Overall results have a margin of sampling error of plus or minus 3.5 percentage points.