But the news isn’t all that sunny. In fact, the mini-exodus from driving has exposed significant cracks in the country’s mass transit systems, which are struggling to accommodate new riders. Having spent decades forsaking the bus and the train for the convenience and privacy of cars, Americans are now finding that the buses, streetcars, trolleys and trains that they left behind are strapped for cash, if they still exist at all.

“All across the country, public transportation systems are experiencing capacity problems,” says Virginia Miller, a spokeswoman for the American Public Transportation Association. “Due to the high costs of fuel, systems’ budgets are being severely impacted.” A survey of 115 of the association’s members found that 60 percent of the systems are considering fare increases, while 35 percent are experiencing service cuts. “It’s ironic that at a time of record ridership we don’t have the funding to expand public transportation systems,” says Miller.

It’s especially lamentable because all those new riders are poised to become mass transit converts. But now, crowded buses and fare hikes could send them back to their cars. “This is going to mean more people out there on the road, driving, creating more congestion for everybody and keeping transportation as our No. 1 source of global warming pollution,” says Stuart Cohen, executive director of Transportation and Land Use Coalition, a grass-roots group based in Oakland, Calif.

To make matters worse, the increase in bus and train ridership is taking place during hard economic times, when transit funding is under the gun. For example, BART has lost $111 million in state funding since 2000, including $37 million in the most recent California budget. “It’s the equivalent of ripping millions of seats right out from under our passengers,” says Luna Salaver, a public information officer for BART.

It’s clear commuters care passionately about service cuts and fare hikes. In Cleveland, 2,000 people showed up at public hearings in August, when the Greater Cleveland Regional Transit Authority, which runs buses, trains and light rail, was considering a 12 percent service reduction and a 50-cent fuel surcharge. An additional 1,000 riders wrote letters to the system. For the past five years, Cleveland has experienced an increase in ridership, while simultaneously getting a 63 percent decrease in state funding. “Our expenses are growing and our income is not,” says Jerry Masek, a spokesman for the Cleveland transit authority.

It’s a story being repeated across the country — a story with a grim irony. California, under the Schwarzenegger administration, has embraced ambitious goals to fight global warming, pledging to bring greenhouse gas emissions down to 1990 levels by 2020. But you wouldn’t know it from how the state is treating transit. Transportation is the No. 1 source of global warming pollution in the state, and it’s the fastest-growing source, yet the state budget recently signed by Gov. Arnold Schwarzenegger and the Legislature raids $1.7 billion from transit funding.

“They’re diverting the money from transit and keeping highways whole,” says Tom Radulovich, a BART director and executive director of Livable City, a nonprofit group that promotes sustainable transportation. “There’s been a big shift to transit as people are trying to avoid high gas prices. But we’re taking billions of dollars away from transit, and investing billions in highways.”

Jeffrey Tumlin, a transportation planner with Nelson Nygaard, a BART consultant, sees the skewed funding priorities as part of a deep-seated bias against transit in American public policy. “If your road or highway is experiencing bad levels of service, it’s assumed that you need to get money to expand capacity,” he says. “When you’re allocating money for transit, nobody ever asks how crowded buses are.”

That attitude is a persistent hangover of America’s romance with the car, which helped transform the nation into a land of suburban sprawl. Back in 1926, Americans each year took 147 transit rides per capita. World War II was a boon to transit ridership, as auto manufacturers were diverted to building tanks and jeeps, and gasoline was rationed. But the postwar prosperity that fed the rise of the automobile and suburbanization meant a dramatic and abrupt spurning of transit by many Americans.

By 1950, Americans took just 113 transit rides per capita, and by 1956 that number had plummeted to just 66. By 2006, Americans took just 33 transit trips a year per capita. In the decades since World War II, it has been only in the dense financial centers, like New York, Chicago and San Francisco, where transit has been able to stubbornly resist the rise of the car, remaining a major way for many residents to get around.

“Big cities were able to fend off the automobile simply because there wasn’t provision made for parking, so transit had a convenience advantage in the largest cities, but nowhere else,” says David W. Jones, a retired historian of transportation policy and management at UC-Berkeley and the author of “Mass Motorization + Mass Transit: An American History and Policy Analysis.” He adds: “The present tendency is to view transit as something good for low-income people.” Or, as the Onion once humorously put it: “Study: 98 Percent of U.S. Commuters Favor Public Transportation for Others.”

While Jones sees evidence that American commuters are returning to public transit because of high gas prices, he says we have a long way to go. “All of the recent highs in transit use have occurred during oil embargoes or oil wars.” In 1960, some 12 percent of all U.S. workers used transit to get to work. By 2000, that number was down to 4.7 percent, and in the past couple of years it has just barely ticked up to 4.9 percent. “To get back to anything significant is going to be a very long haul,” says Jones. The fact remains that fully half of Americans have no access to public transit, according to the American Public Transit Association.

But the revitalization of many American downtowns in recent decades offers hope for improved mass transit. “We’re finding that there is a rapidly growing sector of the market — younger people and aging baby boomers with kids — who are finding the suburbs to be less interesting than when they first moved there, and they’re seeking out the vitality that cities provide,” says Tumlin. “That’s happening all over America.”

Since the early ’80s, 15 major American cities, including San Diego, Portland, Ore., Denver, Houston, St. Louis, Salt Lake City and Los Angeles, have built new light-rail systems from the ground up. Dozens of other cities are considering proposals for similar systems, or have them in development, such as Phoenix and Seattle.

Whether funding can keep up with the new demand for mass transit remains a big question. As does whether gas prices will remain high enough to make riding the train or bus an attractive alternative — one worth fighting for at the ballot box. With the price of oil down 50 percent since July, and gas prices hovering around $3 a gallon, will the return to transit keep on trucking? Or with memories of crowded buses and trains fresh on their minds, will all those new riders get back behind the wheel of their cars?