CHICAGO   -  Donald Trump suggested Thursday that Vice President Kamala Harris had decided to “turn Black” for political gain, as he attacked his Democratic White House rival during a combative and inflammatory interaction with African American journalists in Chicago.

The Republican former president’s provocation marked an escalation of the 78-year-old’s vitriol against Harris, whom he falsely accused of having identified as Indian but then, “all of a sudden, she made a turn, and she became a Black person.” Harris, who has long identified as Black and graduated from a historically Black university, “was always of Indian heritage” but then “happened to turn Black,” Trump told a conference of the National Association of Black Journalists.

“So I don’t know, is she Indian or is she Black?” Trump’s identity assault was at the heart of a hostile interaction with Black reporters, one of whom he berated for asking about his history of offensive remarks about Black people. “I think it’s disgraceful,” he said of the questioning. “I have been the best president for the Black population since Abraham Lincoln.”

The combative remarks by Trump, who has been eager to improve his performance with Black voters, are likely to send shockwaves through the 2024 White House contest.

They come as the former president, convicted two months ago of felony fraud related to hush money payments to a porn star, struggles to formulate a new strategy less than 100 days before the election. He holds a campaign rally later Wednesday in Pennsylvania, a battleground state where he narrowly survived an assassination attempt earlier this month.

The Republican’s White House bid was thrown into chaos on July 21 when President Joe Biden, 81, withdrew his candidacy, backing Harris as the Democratic nominee. Since then, the 59-year-old Harris has seen her favorability ratings jump and raked in $200 million in campaign donations.

Trump, who had placed Biden’s health at the heart of the election, now finds himself up against someone nearly two decades his junior, a trailblazer who became the country’s first Black, female and South Asian-origin vice president.  The seismic shake-up has forced Trump and the Republicans to recalibrate rapidly, and it appears they are struggling to settle on a line of attack. As “Lyin’ Kamala,” “Laughin’ Kamala” and “Crazy Kamala” all failed to stick, Trump’s broadsides have become increasingly incendiary and untethered to reality.

Over the last week, Trump has falsely accused the vice president of being anti-Semitic -- despite her decade-long marriage to a Jewish man, Second Gentleman Doug Emhoff -- and has claimed outrageously that she supports the murder of newborn babies.

The Harris campaign slammed Trump’s Wednesday remarks as “personal attacks and insults” and the latest example of “the same hostility he has shown throughout his life.”

Harris, whose mother was an Indian immigrant and father was Jamaican, has long identified as Black.

“My mother was very well aware that she was raising two Black girls to be two Black women, and she did that instilling in us pride in our culture and cultures,” she said in a 2020 Biden-Harris video.

Trump and Republicans have launched more traditional political attacks, highlighting Harris’s pivots on positions she took while trying to carve out a lane in the crowded 2020 Democratic presidential nominating contest.

Harris no longer supports abolishing private health insurance or a government buyback scheme for guns. She has also disavowed positions against fracking and in favor of expanding the Supreme Court.

“San Francisco liberal @VP Kamala Harris can’t decide where she stands on the most basic issues,” Oklahoma Senator Markwayne Mullin posted on X.

And Trump suggested in an interview this week with Fox News that Harris would be considered weak and “like a play toy” by other world leaders.

“They’re going to walk all over her,” he said.

The messaging appears to have had little impact, as Harris has erased Trump’s lead in multiple key battleground states in the days since becoming the presumptive Democratic nominee, according to a new Bloomberg News/Morning Consult poll. Saturday will see Trump head to Atlanta, Georgia, where he will campaign alongside running mate J.D. Vance.   The 39-year-old senator from Ohio was once a staunch critic of Trump, but changed his tune to become one of his most vocal supporters.

Since Vance’s selection as Trump’s running mate, a series of videos of controversial past statements have emerged, including one in which he mocks some Democratic women as “childless cat ladies.”

Harris travels later Wednesday to Houston, Texas, to address a gathering of African American students.