FORT COLLINS, Colo. » The national debate over the use of the term "illegal immigrant," which has become anathema to people who support relaxed immigration rules, has fixed on an unlikely lightning rod: the liberal-minded, pro-immigrant owner of a Mexican restaurant chain.

The proprietor, Pete Turner, 43, opened his first Illegal Pete’s restaurant nearly 20 years ago, and says that the name was inspired by the name of a bar in a novel and by his late father, also named Pete, who had a rebellious streak. At the time, said Turner, the word "illegal" held little of the political charge it does today.

"I never intended it to be about undocumented immigrants," Turner said. "Never. Not once."

But in opening a new locale here – the chain’s seventh – Turner seemed to have stumbled on a political tripwire he had not known existed, drawing ire from local and national immigrant rights groups that say his use of the word in connection with a person’s name is derogatory and offensive. Furthermore, they said, they are alarmed that an additional Illegal Pete’s is slated to open in Tucson in August.

"The crux of it is that it’s become a racial slur," said Cheryl Distaso, 54, one of a group of local residents who are calling on the owner to change the name. Distaso said she believed that Turner had not meant to offend anyone when he opened Illegal Pete’s in 1995. "But the impact of that word in this day and this town is different," she said, "and ultimately it’s the impact of our actions that we’re responsible for."

The protesters have the support of Race Forward, a national group that began a campaign in 2010 to eliminate the use of the word "illegal" as an adjective for people, particularly in the news media. Race Forward has argued that the term "illegal immigrant" is a tactical term promoted by anti-immigration groups starting in the mid-2000s. The epithet, the group said, is dehumanizing, but quickly moved into the mainstream.

Race Forward’s campaign, "drop the i-word," has had some success. In 2013, The Associated Press announced it would remove "illegal immigrant" from its stylebook. The New York Times revised its policy, encouraging the use of alternative terms but allowing the phrase to be used for "someone who enters, lives in or works in the United States without proper legal authorization."

Fort Collins, about 60 miles north of Denver, is a city of about 150,000 people, about 10 percent of whom are Hispanic. It is also home to Colorado State University, a large research institution with a sizable minority population. This fall, after residents who are sensitive to the word "illegal" heard about the opening of the new restaurant, they urged Turner to meet with them. Among them were professors, students, immigrants and Latinos whose families came here generations ago.

Turner agreed to the meeting, which was civil but emotional. About 45 people attended, with several saying why the word "illegal" was hurtful to them. At least one person cried.

Destiny Story, 21, who is of Mexican descent, recalled having the word hurled at her in a high school dispute. She was born in the United States – as were her parents – but said that her legitimacy in the country is constantly questioned.

"I know he isn’t a racist individual," she said later of Turner. "But I also think there is a time for change."

Kimberly Baker Medina, 53, a local immigration lawyer, moderated the event.

"If you’re a young middle-class white person, you probably don’t think it’s a big deal," she said later. "But if you’re a 60-year-old Chicano, and you, and your parents and grandparents have been victims of racial slurs, it’s a big deal."

Turner said the uproar had caught him off guard. He is particularly troubled by the barrage of supportive emails he has received from people who said they were proudly anti-immigrant. Turner, on the other hand, supports President Barack Obama’s initiatives to change the status of immigrants who are in the country already.

"I believe in all these things that the left has been pushing for, that Obama has been pushing for," he said. "It’s made for some strange bedfellows."

Among his most passionate supporters is Milton Guevara, 30, a Salvadoran immigrant who began working at Illegal Pete’s in Boulder when he was 14. He has risen from dishwasher to general manager. Along the way, Turner helped him acquire a green card, Guevara said, and is now helping him apply for citizenship.

"I don’t see why they think this is offensive," Guevara said, urging the opposition to take a closer look at the origins of the restaurant’s name. "I’m very proud to be working for this company."

Turner said he gave a name change real consideration.

"I had to check myself," he said, "and to be honest, I did. I have integrity, and when I said I’d listen, I did."

In early November, though, he announced in a lengthy letter on the restaurant’s website that he had heard the concerns of the opponents, but that their interpretation of the name did not change his own view of it.

"The name to me was unique and countercultural," he wrote, "which I appreciated as a younger man. Still do. It’s typically the countercultural places in our society that are the most accepting of individuals from all different walks of life."

And on Thursday, he opened Illegal Pete’s in Fort Collins to a crush of enthusiastic patrons.

By 11:45 a.m., the airy, warehouse-style restaurant was packed, despite record-shattering low temperatures. Several women bellied up to the bar and ordered local brews. Employees working the burrito line operated sandwich irons that heated giant tortillas. The crowd tended to be young, white and tattooed, though there were also families and older couples.

"There was no debate for us," said Brett Warr, 47, who works in information technology for the city, explaining that he did not understand the fuss. "It’s not called ‘the illegal immigrant.’"

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