Robert F. Kennedy Jr. plans to hold a news conference Friday in Phoenix to announce his exit from the presidential race, according to multiple media outlets, which also predicted that the scion of America’s greatest Democratic political dynasty would throw his support behind the Republican nominee, former President Trump.

It’s unclear how Kennedy‘s exit would affect the presidential race. A Pew Research Center poll this month suggested that Vice President Kamala Harris has picked up would-be Kennedy supporters. It appeared that backing came in some measure from women and non-white voters who previously were leaning toward Kennedy.

But Trump allies say the Kennedy endorsement would be a victory. “Fox & Friends” host Brian Kilmeade said Friday morning that the Republican would surely pick up a critical 2 or 3 percentage points with Kennedy’s support. That would be enough, Kilmeade insisted, to swing the campaign back into the GOP’s favor.

Trump is campaigning in Arizona on Friday and posted on social media that he would have a “special guest” at an afternoon rally. On Thursday, Kennedy withdrew from the ballot in Arizona.

Kennedy, a 70-year-old Los Angeles resident, entered the race in April 2023, with a burst of media attention. He showed unusual strength in some early polls for a candidate with no experience in elected office. But his support flagged after Harris emerged last month as the Democrats apparent nominee.

Kennedy’s thoughts about leaving the race became public in recent days, when his vice presidential running mate, Nicole Shanahan, discussed those talks. She said Kennedy might accept a position in a Trump administration, in particular if he thought it could help combat what she called an epidemic of chronic disease.

The transition to Trump stalwart will be greated with skepticism in many circles, given Kennedy’s political DNA and his past description of the Republican as “unhinged” after Trump went on a social media tirade, accusing Kennedy of being a “Democrat plant” and “wasted protest vote”.

“When frightened men take to social media they risk descending into vitriol, which makes them sound unhinged,” Kennedy wrote on X in April. “President Trump’s rant against me is a barely coherent barrage of wild and inaccurate claims that should best be resolved in the American tradition of presidential debate.”

Kennedy’s presumed exit from the race comes 16 months after he stood before the media in Boston, scene of many political triumphs for previous generations of the Kennedy clan, which included his father, the New York senator and attorney general and his uncle, President John F. Kennedy.

The long-time environmental attorney initially ran as a Democrat. But by October 2023, Kennedy said that he would run as an independent, because party nominating rules made it too difficult to compete, particularly against an incumbent like President Biden.

Kennedy said his independent status would allow him to break the grip on power held by a virtual “uniparty” — the Democrats and Republicans — and that he would be in a better position to cut out-of-control government spending, to take on “Big Pharma” and other corporate interest and to invest more in reversing America’s epidemic of chronic illness.

Even after his shift to an independent campaIgn, and as he courted support from smaller political parties, polls showed Kennedy unable to move within reasonable striking distance of his big party rivals.

Kennedy argued that he should be allowed into the June debate between President Biden and Trump, but he could not persuade the other candidates or networks that he had earned a place on the stage.

Kennedy’s campaign also spent abundant time and money trying to qualify him for the ballot in all 50 states. He suffered a setback last week when a New York judge ruled he shouldn’t appear on the ballot because he listed a “sham” address on nominating petitions.

Thought he presented himself as a pragmatic problem solver, not beholden to big interests, Kennedy’s views on some issues — particularly vaccines — were extreme. A particularly problematic example: When he compared Biden’s vaccine policies to the Holocaust. He suggested that Jews, including Anne Frank, had more freedom under the Nazis than Americans living with COVID-19 mandates.

That drew rebukes from many Jewish groups and even a complaint from his wife, actor Cheryl Hines, who called the Frank reference “reprehensible and insensitive.” Kennedy apologized.

Though born into what some viewed as an American political “Camelot,” Kennedy struggled as a young man, particularly with his 14-year addiction to heroin. The candidate sought to use that ordeal to his advantage, saying that his 40 years in recovery made him uniquely qualified to bring new solutions to the nation’s addiction crisis.

But other aspects of his past, including his past relationships with women, became fodder for new criticism.

That included the regurgitation of a 2013 New York Post story, after the tabloid somehow acquired a journal that RFK Jr. allegedly kept in 2001. It included a log of 37 women that he had sex with when he was married to Mary Richardson Kennedy, the Post and other outlets reported.

(Kennedy’s wife had killed herself in the year prior to publication of the story, but she had reportedly found the journal at some point.)

Early last month, reports about the disturbing behavior resurfaced in a Vanity Fair profile, in which a former family babysitter described how Kennedy groped her when she was in her early 20s and taking care of Kennedy’s four children with Mary. Text messages revealed that the candidate apologized to the former babysitter after publication of the article, though he told reporters he recalled nothing about the alleged misconduct.

Then, in August, a New Yorker profile revealed an odd Kennedy prank. As a grown man, the man known – like his father — as Bobby, once retrieved a dead bear cub from a roadside and deposited the corpse in New York’s Central Park. The carcass provoked a mystery that consumed the city a decade ago.

Kennedy faulted both Biden and Trump, as he criss-crossed the country, trying to spark the kind of momentum his father did in the 1968 race for the White House. But he increasingly lashed out at Biden and the Democrats more, particularly infuriated by the challenges they lodged to his ballot petitions.

As recently as Wednesday, the candidate sent messages like a man still in the fray. One came via a video posted on social media, when he invoked Abraham Lincoln and said “we must realign ourselves with the founding spirit of our nation.”

On Thursday, Shanahan again nodded to the duo’s possible exit from the race. She seemed to relish the way some of her friends pleaded with her not to support Trump.

“My old Dem buddies have been flooding me with frantic calls, texts, and emails,” she wrote on the social media platform X. ”The message was clear: they’re terrified of the idea of our movement joining forces with Donald Trump. When I point out what the Democratic Party and their super PACs have done to sabotage our campaign, their response is always, ‘but Trump is worse.’ Here’s an idea: stop suing us. Let us debate.”

She then suggested, without providing evidence, that the Democrats somehow were “rigging the media and the polls” — the sort of accusations Trump has made many times in the past.

Trump gave no clear indication Thursday of how he might partner with Kennedy. Following Harris’ address to the Democratic convention, the former president went on Fox News for a phone interview.

“I’ve had a great relationship with him over the years. I respect him. He respects me,” Trump told Fox anchor Brett Baier. “I have no idea if he’s going to endorse me.”

He said the Friday appearance of both men in Arizona was a coincidence. “But it’s possible we will be meeting tomorrow,” Trump said.