(Associated Press Photo)

SIOUX CITY, Iowa (AP) — Democratic presidential candidate Elizabeth Warren offered a public apology Monday to Native Americans over her past claim to tribal heritage, directly tackling an area that's proved to be a big political liability.

"Like anyone who has been honest with themselves, I know I have made mistakes," the Massachusetts senator said at a forum on Native American issues in this pivotal early voting state. "I am sorry for the harm I have caused."

Monday's remarks were an effort to move past the fallout from her past claims of tribal ancestry, which culminated in a widely criticized release of a DNA analysis last year. The issue nearly derailed her campaign in the early days as President Donald Trump began derisively referring to her as "Pocahontas."

Now that Warren is gaining in most polls, she's trying to prove to voters that the controversy won't doom her in a general election matchup against Trump. The detailed policy agenda to help Native Americans that she released last week helped her secure a warm reception from attendees at the tribal forum.