Sen. Scott Brown, R-Mass., left, shakes hands with his Democratic challenger Elizabeth Warren, right, on the set before their first debate as moderator Jon Keller observes on Sept. 20, 2012, in Boston. (Michael Dwyer/AP)

For the first time that Laurie Weahkee can remember, Native American heritage has become an issue in national politics. Under other circumstances, that might be welcome. But in this case, Weahkee, a Navajo, Zuni and Cochiti Pueblo in New Mexico, is appalled at what she is hearing.

Sen. Scott Brown (R-Mass.) has focused his reelection campaign’s attention on the self-proclaimed Native American heritage of his Democratic challenger, Harvard Law School professor Elizabeth Warren. Years ago, Warren listed herself as a Native American in professional directories commonly used by recruiters.

Her claims set off a controversy in the campaign, one of the most closely watched races in the country. A Boston Globe poll released Sunday showed Warren leading Brown by 43 percent to 38 percent. Eighteen percent were undecided.

Brown brought Warren’s lineage back into the spotlight with his remarks in a Sept. 20 debate and in an ad using old news accounts to renew skepticism about his opponent’s ancestral claims. The two politicians will meet for their second debate Monday.

Warren responded with an ad of her own, saying: “As a kid I never asked my mom for documentation when she talked about our Native American heritage. What kid would?”

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Brown has apologized for staff members doing the “tomahawk chop” outside a political rally. And Warren has aired a campaign ad explaining that she never benefited personally from her claim of Cherokee and Delaware heritage.

This political soap opera playing out on the East Coast has triggered a robust conversation among Native Americans across the country — some of whom feel that their culture has become a political football.

“Nationally, it just looks ridiculous,” said Weahkee, who has been following the race with interest and more than a little chagrin.

Warren’s assertion of her family’s history has tapped into a larger issue for Native Americans around the murky understanding of ancestry. They have watched a growing number of people embrace Native American heritage in a steady demographic trend.

From 1960 to 1990, the number of Americans claiming to be American Indians more than tripled to 1.8 million, according to census figures. In the 2000 Census, which for the first time allowed people to mark more than one race, 4.1 million Americans said they were at least partly Native American.

In Oklahoma, where Warren is from, her story came as no surprise, said Amanda Clinton, spokeswoman for the Cherokee Nation.

“This is a very common claim,” said Clinton, who noted that Cherokee citizens must be directly descended from tribal members listed on the Dawes Rolls between 1898 and 1914. Warren’s family is not found there.

“However, we do not feel it is the tribe’s place to second-guess someone’s family tree,” she said. “There is a big difference between citizenship and heritage.”

Tribes have differing criteria for membership, some with “blood quantum” requirements specifying minimum degrees of ancestry. Others, such as the Cherokees, do not — but tribal members must trace their direct lineage to someone on an earlier tribal membership roll. Tribes issue their members identification cards, and the Bureau of Indian Affairs issues Certificates of Degree of Indian Blood.

The New England Historic Genealogical Society found a family newsletter that alluded to a marriage application listing Warren’s great-great-great-grandmother as Cherokee. But the application itself was not found.

The Boston Globe interviewed an extensive list of the professor’s relatives, who had conflicting memories. Some recalled stories of Indian ancestors; others did not.

Suzan Harjo, a columnist for the Indian Country Today Media Network, said that she admires Warren’s politics but that the Democrat’s claims of heritage raised all kinds of questions. If Warren considered herself Native American, what did she do for the community she claimed?

“Anyone who is a person of color and anyone who is in academia knows what a box checker is,” said Harjo, who is also president of the Morning Star Institute, a national Native American rights organization. “When I heard that it was likely that she did that, I was floored.”

Harjo called friends and Native American groups in Oklahoma, Michigan and Massachusetts to see what Warren’s interactions had been with the community. “No one knew her,” Harjo said.

Harjo, who was in the forefront of the fight against the Washington Redskins’ team name and tried to get the trademark yanked, agrees with political analysts who have said Warren has mostly bungled her handling of the issue. At one point, Warren cited her “high cheekbones” as evidence of her indigenous ancestry and said she listed herself as a minority in the professional listings merely to connect with “people like me,” noting that it was “not a particularly good use for the directory, because it never happened.”

Warren’s decision not to meet with Native American groups that wanted to talk to her at the Democratic National Convention also rubbed Harjo the wrong way, and Harjo found herself agreeing with Brown.

Then, in the first debate of the campaign, Brown said Warren “checked the box claiming she was Native American, and, you know, clearly she’s not.” By seeming to judge Warren’s ancestry from her appearance, Brown had committed his own error, Harjo said.

“They both botched it by making it racial,” she said.

As one of the nation’s smallest minorities — and a people whose tribes have a sovereign relationship with the federal government — Native Americans have had to deal with a unique set of challenges, Clinton said.

“Everybody thinks we’re extinct, that we’re historical figures and not real people,” she said.

Others in the Native American community who are working to bring attention to issues affecting their community this election season said they, too, are frustrated. The National Congress of American Indians held “Native Vote Action Week” last week to try “bring together Indian Country in an effort to raise awareness about the importance of civic engagement and increase Native voter participation.” But there is fear that the conversation about tomahawk chops and distant heritage is taking the wind out of more important issues facing Native Americans.

“It would be nice if [the Massachusetts contest] gave people pause to even think about the fact that there are real Native people and real Native nations and pressing issues in Indian country today,” said Tsianina Lomawaima, a professor of American Indian studies at the University of Arizona who is of Muskogee (Creek) Nation heritage. “If this were an avenue to lead them to that kind of recognition, that would be swell. I’m not betting a lot of money on that.”

Alice Crites contributed to this report.