Massachusetts Democratic Sen. Elizabeth Warren indicated her race was “American Indian” in a handwritten registration form filed in 1986 with the Texas State Bar, according to a new report on Tuesday that documents the presidential hopeful’s efforts to identify as a minority during her earliest days as a law professor.

The revelation, initially reported by The Washington Post, is the first known instance of Warren claiming Native-American ancestry in an official document or in her own handwriting.

It threatened to add more ammunition to already-frequent attacks by Republicans, including President Donald Trump, deriding Warren for claiming such ancestry to bolster her academic career.

Warren’s office, questioned by The Post, did not dispute the authenticity of the bar card.

Last week, Warren apologized to the Cherokee Nation for taking a DNA test in an attempt to prove she had Native-American ancestry, and on Tuesday, she again more broadly apologized for identifying as Native American “for almost two decades,” according to The Post.

Republicans characterized Warren’s apologies as politically motivated and insincere.

“For the seven years this has been in the news, Elizabeth Warren has refused to apologize. Now, four days before her formal presidential launch, she’s issued a politically opportunistic apology that doesn’t go nearly far enough,” Republican National Committee (RNC) spokesman Mike Reed said in a statement, referring to Warren’s plan to formally begin her campaign for the White House on Saturday.

“Warren pretended to be a minority to climb the Ivy League ladder — a lie that will continue to haunt her presidential ambitions.”

The bright-yellow bar card is dated April 1986, when Warren was a professor at the University of Texas School of Law.

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Past reporting by several outlets, including CNN, had indicated that Warren “had not” listed herself as a minority in her “student applications and during her time as a teacher at the University of Texas.”

Records unearthed by The Boston Globe found that in 1981, 1985, and 1988, personnel forms at the University of Texas showed that Warren had called herself “white.”

Related: Elizabeth Warren Is Still Worth Millions

The State Bar document, which functions as a kind of directory entry for lawyers, is among multiple instances in which Warren described herself as a Native American.

She indicated that she was Cherokee in an Oklahoma cookbook called “Pow Wow Chow” in 1984, and listed herself as a minority in the Association of American Law Schools Directory of Faculty from 1986 to 1995 — a move she said later was an effort to “connect” with other “people like me.”

Warren dropped off the list in 1995, after moving to Harvard Law School. But in 1996, an article in the student-run Harvard Crimson apparently indicated that faculty members and administrators still believed Warren was Native American.

“Although the conventional wisdom among students and faculty is that the Law School faculty includes no minority women, Chmura said Professor of Law Elizabeth Warren is Native American,” the article stated, referring to Harvard spokesman Mike Chmura.

And a 2005 document obtained by The Hill indicated that the University of Pennsylvania Law School considered Warren among its past minority faculty members. Warren, who had resigned by the time the university published that document, taught at the law school in the 1980s and 1990s before taking a professorship at Harvard.

Through it all, Warren has maintained that she did not use her claims of ancestry to advance her academic career. An extensive investigation by the Globe did not support the contention that Harvard had relied on Warren’s’ claims of Native American heritage in deciding whether to hire her.

Randall Kennedy, a law professor in charge of recruiting minority candidates at Harvard at the time, told the Globe that Warren was never considered a minority for hiring purposes.

“She was not on the radar screen at all in terms of a racial minority hire,” Kennedy said. “It was just not an issue. I can’t remember anybody ever mentioning her in this context.”

Warren’s prospective presidential candidacy has had a rocky start since she announced that she had formed an exploratory committee for a White House bid on Dec. 31. That evening, Warren was widely mocked for appearing in an Instagram live feed and awkwardly telling the audience, “Hold on a second — I’m gonna get me a beer.”

Warren’s’ husband later walked into the kitchen, prompting Warren to tell him, “Thank you for being here.” He replied, matter-of-factly: “Enjoy your beer.”

Trump later savaged the episode as “the Elizabeth Warren beer catastrophe.”

On Tuesday, filings revealed Warren is worth more than $4 million — complicating her effort to appeal to working-class voters with proposals like an unprecedented tax on wealth. in January, Warren proposed an unprecedented tax of 2 percent annually on all assets belonging to households worth more than $50 million, as well as a 1 percent tax on households with $1 billion or more.

Critics have charged that the idea is both dangerous and unconstitutional because it directly taxes wealth that is not transferred, invested, or earned as income, without ensuring the tax is evenly distributed across states.

And over the weekend, Harry Reid, the longtime Democrat who represented Nevada in the Senate for three decades and served as the Senate majority leader for eight years, declined to endorse Warren’s nascent presidential run.

Although he called Warren a “good person” in an interview with The Boston Globe, Reid, 79, asserted that “my Nevada politics keep me from publicly endorsing her.”

He added that “anything I can do to help Elizabeth Warren short of the endorsement, I will do.”

Reid helped catapult Warren into the national spotlight by appointing her in November 2008 to the Congressional Oversight Panel, a five-member committee responsible for overseeing the federal bailout provided by the Emergency Economic Stabilization Act.

Gregg Re is an editor for Fox News. This Fox News piece is used by permission.

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