At a recent Asia Society forum showcasing American culture for Chinese audiences, the most sought-after celebrities for a quick handshake or a random cellphone photo were the cellist Yo-Yo Ma, actress Meryl Streep, filmmaker Joel Coen and, of course, Gary Locke.

Gary Locke?

Yes, that Gary Locke. The low-key, two-term Washington state governor and former Obama administration commerce secretary who — with his wife, Mona Locke, and their three children — has become in just three months something of a media and Internet star in China as the first U.S. ambassador of Chinese ancestry.

Locke’s popularity here among ordinary Chinese, as expressed by random comments in interviews and posts on popular microblogging sites called weibo, has as much to do with his unassuming nature — his ordinariness — as his Chinese looks and background. Even before he arrived, Locke was photographed with his daughter at the Seattle airport, sporting a backpack and trying to pay for his coffee with a coupon.

Since then, Locke “sightings” have included the ambassador flying in economy class, buying ice cream with his daughter in the Sanlitun neighborhood of Beijing, and waiting in line with his family alongside tourists for a seat on a cable car descending from the Great Wall.

The reason for the fascination, many here posit, is that when Chinese look at this backpack-toting American envoy with a Chinese face, they see everything their own leaders are not — leaving authorities struggling for how best to respond to his increasingly evident popularity.

Ask about Locke’s maiden speech as ambassador to the American Chamber of Commerce, in which he challenged China to reform its foreign investment policies and protect intellectual property, and you might get blank stares. But almost everyone knows about the backpack, the Starbucks coupon, the cattle-class airline seat.

“I was really impressed by Gary Locke’s simplicity,” said Liu Changge, a 21-year-old Beijing parking lot security guard wearing an oversize green uniform. “My first impression of him is the picture circulating online of he, his wife and their children in the airport. Each of them carried big pieces of luggage. It’s unimaginable for a high Chinese official to move abroad like that.”

Mona Locke also has been in the news, with many netizens re-tweeting the fact that her grandmother Lan Ni was the second wife of the son of China’s revolutionary hero, Sun Yat-sen. “I don’t think she has really made her presence felt yet,” said Hong Huang, a fashion magazine publisher.

“It was completely unexpected, and not by design,” Gary Locke told reporters in Guangzhou who accompanied him on a trip — his first as ambassador, his third overall — to his ancestral village of Taishan. “I’m somewhat overwhelmed by the microblogging that takes place in China, and the smartphones and all the people that want to take pictures of myself and my family.”

“It shocked us even before he flew to Beijing, someone snapped his picture at Starbucks,” said Michael Anti, a journalist and blogger in Beijing. The shock, Anti said, was that many Chinese believed that Locke, as the top U.S. diplomat in China, “should be like Chinese officials — he shouldn’t use coupons, and he should have bodyguards.”

“He takes his daughter to school,” Anti said, in a country where the families of officials are rarely seen in public — and many of the senior leaders send their children abroad to schools in the United States or London. “It just shows the opposite picture of Chinese officials, just like a mirror. But the mirror is not good for Chinese officials.”

Locke’s “low-key and simple style makes a sharp contrast with Chinese officials,” said Hu Xingdou, a professor of economics and Chinese issues at the Beijing Institute of Technology. “People are expressing their dissatisfaction with officials and the corrupt system by praising and supporting Gary Locke.”

Hu added, “He should be the most influential U.S. ambassador to China.”

Given Locke’s prominence, it’s not surprising that China’s leadership and official media have seemed uncertain how to respond — and some of the results have been ham-handed.

For example, on Aug. 15, the Guangming Daily — a Communist Party newspaper in Beijing — ran a commentary under the headline: “Be Vigilant to Neo-Colonialism of America Brought by Gary Locke.”

“No followers, no guards, no flowers, no applause or warm welcoming extravagant show, the family just arrived in Beijing with luggage, just like ordinary people,” the commentary said of Locke’s arrival. “Obviously, such kind of style will gain the hearts of ordinary Chinese more.”

But it warned, “His Chinese blood attracts the eyes of Chinese around the world, enables him to win public opinion.” And, it said, “Who knows that this just exposes the evil purpose of the U.S., to use a Chinese to play off against Chinese and to instigate political turbulence in China?”

Another Communist Party-owned newspaper, Global Times, followed up with an unsigned editorial Sept. 22 attacking Locke’s unassuming style.

“Some journalists like to romanticize what they see out of a lack of knowledge and may hold Locke up as a mirror for Chinese officials,” the editorial said. “Locke himself should have purposely avoided being treated as a mirror.” It added: “A U.S. ambassador becoming a political star in China cannot be interpreted as U.S. respect for China.”

The reaction to the two articles was fierce, with readers defending Locke, in written letters and online.

“Why treat the ambassador with such mistrust, skepticism, and hostility?” one reader, identified as “D. Chang,” wrote to the Global Times. “ . . . Maybe the reason why the ambassador is like this, is because this truly is the way he lives?”

The backlash was so strong that the Guangming Daily commentary attacking Locke has been deleted from the paper’s Web site.

Other attacks against Locke have boomeranged. At a diplomatic conference in Guangzhou on Nov. 15, Zhao Jinjun, president of the China University of Foreign Affairs and a former Chinese ambassador to France, criticized Locke’s decision to fly economy class.

“Our country has a different opinion,” Zhao said. “We believe more that the ambassador represents the country, so I must fly the first class if I go out as an ambassador.”

Zhao’s comments were roundly denounced by netizens, and the main microblogging site, Sina Weibo, censored thousands of angry responses.

There now appears to be a concerted effort by the government’s censorship bodies — collectively referred to by critics here as the “Ministry of Truth” — to limit coverage of Locke in the official state-run media.

“We received the order from the propaganda department about Gary Locke, when he was criticized by the party newspaper,” said the editor of a Beijing news Web site, who spoke on the condition of anonymity to discuss the details of official censorship in China. “It’s an oral order. They said not to cover everything about Gary Locke. Don’t over-report him.”

Some Chinese media have also tried to link Locke to a business dispute between a Ningbo-based lighting company called Geosun and another firm, EML Technologies, owned by Wade Lee, brother of Mona Locke. Geosun is suing EML in the United States and China over an $11 million debt it says it is owed, and has used its weibo account to draw publicity to the case, saying Locke, as governor, visited Geosun with his brother-in-law.

Richard Buangan, a U.S. Embassy spokesman, said the suit has nothing to do with Locke. “The ambassador was never asked to support the company. He was never asked to advocate for the company,” he said.

Ever since President Obama named Locke to replace Jon M. Huntsman Jr., who resigned as ambassador to run for president, questions have surfaced about whether the Chinese American’s background might lead to dual loyalties. (Ironically, Locke may look the part, but he does not speak Mandarin, whereas his predecessor in the job did.)

But Locke’s toughly worded challenges to China — on everything from its currency to intellectual property protection to leveling the playing field for U.S. businesses here — seem to have dispelled any notion that he is anything other than an envoy for American interests.

“He made it pretty clear from day one that he’s an American first of all,” said Hong Huang, the fashion magazine publisher. His public speeches, she said, “completely dashed any Chinese expectation that he would behave any differently from any other American ambassador because he is Han Chinese ethnically.”

In his speeches, Locke pays homage to his Chinese roots, and how 100 years after his grandfather left his ancestral village to become a houseboy in Washington state, Locke was elected the state’s governor, and the first Asian American governor on the U.S. mainland.

Much like Barack Obama did when he was running for president in 2008, Locke tells his story as an example of the American ideal of openness and inclusiveness. “I’ve sometimes asked myself: ‘How did the Locke family go in just two generations from living in a small rural village in China to the governor’s mansion?’ ” Locke said in a Sept. 9 speech to students at Beijing Foreign Studies University. “The answer is American openness — building and sustaining an open economy and an open society.”

“Our family’s story is the story of America,” Locke said. And, in a subtle challenge to China to become more open, he added, “we believe these values are independent of any particular political system. They are universal, and universally beneficial to societal advance.”

“He did affect people’s views about America in a positive way,” Hong Huang said. “It’s shown people that America is a society that gives the underdog a chance to rise to the top.”

She added, “He’s a prime example of the American dream.”

Washington Post researcher Zhang Jie contributed to this report.