The low point, said Rogers, 25, a medical researcher who now pedals 6 miles to work every day, was when a pedestrian punched her as she biked down Commonwealth Avenue in Brighton. But in Portland, she said, a city that prides itself as the most bike-friendly in the nation, “you’re not weird’’ for biking.

Crisscrossed with bike lanes and streetcar tracks, Portland has long attracted the young and environmentally conscious with its cutting-edge transportation system, which has resulted in 20 percent less driving than the national average. But whether Portland’s unorthodox mix of policies can be exported, as the Obama administration hopes, remains to be seen.

“The question is, can you adopt the personal culture of Portland that embraces those modes in other places, and how do you do that? That’s a challenge, but certainly one we have to try to meet,’’ said James A. Aloisi Jr., the Massachusetts transportation secretary.

Officials in Portland say the recognition from Washington is long overdue after years in which federal bureaucrats were indifferent or hostile, even as the city’s emphasis on “livability’’ became widely admired among urban planners and environmentalists. And while boasting of Portland’s transit-oriented culture, officials largely reject the idea that there is something special in the Oregon air that can’t be replicated elsewhere.

“We happen to have gone down a path that was very prescient,’’ said the city’s mayor, Sam Adams, formerly a city transportation official. “We get high praise on a very low standard.’’

The Obama administration’s focus on Portland, which US Transportation Secretary Ray LaHood dubbed the “capital city’’ of transportation policy during a visit last month, comes as Congress begins work on a new six-year highway and transit bill. Advocates hope the law, which could be voted on as early as this fall, will be the most sweeping overhaul since 1991.

A draft, written by the House Transportation and Infrastructure Committee chairman, Jim Oberstar, a Minnesota Democrat, would establish an of “office of livability’’ to evaluate transit proposals, music to the ears of Portland officials who have been frustrated by federal policies they see as drastically tilted in favor of cars.

“It feels like vindication,’’ Adams said.

Portland’s bike policies have also cropped up in the health care debate, when Senate Democrats inserted language into a bill to pay for bike lanes. Republican critics said the provisions had little to do with health care, but advocates said they would contribute to overall public health, citing Portland as an example.

“What was controversial at one point for Portland is now increasingly mainstream,’’ said Representative Earl Blumenauer, a Democrat who represents Portland in Congress and is the founder, chairman, and eminence grise of the congressional bike caucus, which supports probicycling policies.

Portland’s distinctive approach to transportation emerged in the 1970s, when city residents revolted against plans to build a new freeway through downtown. Instead, taking advantage of a loophole in federal highway law, officials diverted the funding to a light rail system - the first newly constructed system since World War II and a model for similar projects in cities including Baltimore and Seattle.

Now, orphaned onramps stand alongside Portland’s freeways, connections to highways that were either never built or torn down and concrete symbols of the different direction the city has chosen.

Since then, the city has built 300 miles of bike lanes, and as a result, has biking rates that are eight times the national average. They built more than 1,000 speed bumps and traffic barriers to slow vehicles and protect bikers and pedestrians, bringing overall traffic fatalities to the lowest level since recordkeeping began in 1925. A streetcar line connecting two once-industrial neighborhoods, also the first new project of its type since World War II, opened in 2001; officials had to build it with all local money after the Clinton administration refused to fund the project.

Still, skeptics wonder whether Portland is just filling a niche and attracting bicyclists from elsewhere, instead of changing the habits of residents. Perhaps its bikes and trolleys are merely part of its quirky, offbeat image - to go with its vintage clothing shops, farmers’ markets, and lax drug enforcement. By definition, they argue, not every city can be a “capital city’’ of anything. Indeed, an informal survey of bike commuters at the city’s Hawthorne Bridge, a popular cycling route, found that like Rogers, almost all of them had grown up somewhere else and then moved to Oregon.

Graphic designer Brad Reber, 40, a self-described “Portland stereotype,’’ moved to the city from Atlanta three years ago and said he hasn’t driven his car in more than a year.

“I said to myself, ‘Dear God, there’s got to be a better way to live,’ ’’ he recalled. Overall, one study found that 4.6 percent of Portlanders lived somewhere else the previous year.

But Metro Councilor Rex Burkholder - a bicycling activist and himself a former Boston resident - said that while many had undoubtedly moved to the city for its amenities, thousands of longtime residents had switched from driving to light rail or cycling.

“We’re not draining the world of people who like to ride bikes,’’ he said. “It’s facilities that make people switch over, not philosophy.’’

Even if they could be replicated, however, the city’s policies have also made it a lightning rod for criticism from conservatives, who have derided the administration’s embrace of the city. Newsweek columnist George Will referred to Portland as “the P word’’ in a column in the spring and accused officials of pursuing “behavior modification’’ to coerce people out of cars.

In an interview with the Globe, LaHood said that such critics were “living in the past’’ and that continuing to build more highways was also coercive. “We’ve created a system that requires people to get in their cars if they want to get anywhere,’’ he said.