Alva Review-Courier -

LAWTON, Okla. (AP) — Democratic presidential candidate Bernie Sanders is focusing on reliably Republican Oklahoma with an appearance before the largest annual gathering of the Comanche Nation in the state where rival Elizabeth Warren was born.

Sanders' visit may remind some of a sensitive subject for Warren, still criticized after her October release of a DNA test meant to bolster her claim to Native American heritage. That was supposed to rebut President Donald Trump's mocking of the Massachusetts senator as "Pocahontas," but only intensified it.

Last month, Warren offered a public apology to Native Americans, trying to show that the issue won't be a political drag in her White House campaign.

The Comanches, who are holding their 28th annual Nation Fair Powwow, are a Plains Indian tribe of about 17,000 enrolled members, with headquarters just north of Lawton, in southwest Oklahoma. Powwows are important social events for many tribes, and typically feature traditional dance, songs, food, regalia and other customs.

Sanders, a Vermont senator, won Oklahoma's 2016 Democratic primary over Hillary Clinton. The state votes next year as part of the earlier and expanded "Super Tuesday," which comes on March 3 and includes neighboring Texas.

University of Oklahoma political science professor Keith Gaddie said Sanders' powwow visit was unusual because the tribe, which well-known, is not a particularly large Native American nation.

"There's no reason, in order to win the state, that you'd have to go down to that event," Gaddie said.

Warren has made her family's down-home, financial struggles after her father had a heart attack and couldn't work — forcing her mother to get a minimum wage job — a central theme of her campaign. Sanders and Warren are friends who agree on many policy issues, including the "Medicare for All" universal health insurance plan.

Both also have refused to attack one another, ducking questions about whether they eventually will have to compete for the Democratic Party's most liberal wing. But a Des Moines Register-CNN-Mediacom poll released Saturday showed Warren outpacing Sanders in Iowa, which launches the 2020 Democratic nominating contest on Feb. 3, and running about even with former Vice President Joe Biden, who had been the crowded field's front runner.

Sanders planned a rally at the University of Oklahoma before speaking at the powwow.