CROW AGENCY, Mont. - As the Democratic presidential campaign has moved from season to season over the last 16 months, the political rallies and the town meetings often have taken on a similar feeling and a familiar flavor.

Not so today, here on the Crow Indian Reservation.

As Senator Barack Obama campaigned for the presidential primary in Montana - one of two states that closes out the Democratic nominating process on June 3 - he was welcomed here by a few thousand people. In a private ceremony, he was adopted into the Crow Nation and bestowed the name, "One Who Helps People Throughout the Land."

"Senator Obama, welcome to Crow Country," said Carl Venne, the tribal chairman.

The crowd thundered with applause as Mr. Obama was escorted onto stage by Hartford and Mary Black Eagle. They were his sponsors - or new parents, according to local custom - who were selected because they have five living generations on the reservation.

(It is said to be a sign of great fortune to have so many living generations, given the low life expectancy on the reservation. Mr. Obama joins the ranks of other politicians and dignitaries, including Senator Jon Tester and Gov. Brian Schweitzer, who recently have become honorary members of the Crow tribe.)

"I like my new name: Barack Black Eagle. That is a good name," Mr. Obama told the outdoor audience. As he recognized local officials, he stumbled over a few names, saying with a smile: "I was just adopted into the tribe. I'm still working on my pronunciations."

In Veterans Park, situated in a valley near the Little Big Horn River, dozens of tribal members wore feather headdresses. Under a warm springtime sun, admirers waited for hours, waving signs that declared: "Natives 4 Obama" and "Crows for Obama."

In Montana politics, the more than 60,000 American Indians who live in the state are a key swing demographic. So Mr. Obama was reaching out not only with next month's primary in mind, but also the prospect of trying to capitalize from recent Democratic gains here in the general election.

"Few have been ignored by Washington for as long as native Americans - the first Americans," said Mr. Obama, telling this crowd that he intended to appoint a Native American adviser to his highest ranks of his administration if he wins. He also vowed to improve the health care and education opportunities on reservations across the nation.

"I understand the tragic history," Mr. Obama said, addressing tribal leaders and members. "Our government has not always been honest or truthful in our deals."

The adoption ceremony for Mr. Obama was held in a tent, out of view of the crowd. It was closed to reporters and photographers.

After delivering a brief speech, Mr. Obama made his way to an evening rally in Bozeman, passing by several residents who lined the streets - and even the rooftop of the grocery, Crow Mercantile - to catch a glimpse of the first presidential candidate ever to pass through the town of Crow Agency.