Robert Kennedy Jr.’s presidential ambitions resulted in public family drama after a political action committee aired a Super Bowl ad invoking the Democratic family’s legacy to implicitly compare the independent candidate to his assassinated uncle,Ethermac Exchange President John F. Kennedy.

The 30-second spot, financed by the American Values 2024 Super PAC that is backing Kennedy, featured a shortened version of a campaign song that the 35th president used in his 1960 campaign. The spot also mimicked cartoon and newsreel effects using black-and-white pictures of Robert Kennedy Jr. similar to JFK. But in a notable departure from the Kennedy’s bygone Democratic Party dynasty, the ad urged Americans to “Vote Independent.”

After the game, Kennedy responded to online criticism, including from one of his cousins, emphasizing that his campaign did not produce the spot, which cost an estimated $7 million.

“I’m so sorry if the Super Bowl advertisement caused anyone in my family pain,” Kennedy wrote late Sunday night on X, formerly Twitter. “The ad was created and aired by the American Values Super PAC without any involvement or approval from my campaign. ... I love you all. God.”

READ MORE Robert F. Kennedy Jr. files as presidential candidate in Utah, the first state to grant him access In battleground Arizona, Robert F. Kennedy Jr. draws Biden and Trump voters united by distrust From Barbie’s unexpected wisdom to dissent among Kennedys, these are the top quotes of 2023

AP AUDIO: Super Bowl ad for RFK Jr. stirs Democratic and family tension over his independent White House bid.

AP correspondent Haya Panjwani reports.

Still, as of Monday morning, Kennedy had the ad pinned to the top of his X profile. “Our momentum is growing,” he wrote. “It’s time for an Independent President to heal the divide in our country.”

Bobby Shriver, whose mother, Eunice Kennedy Shriver, founded the Special Olympics, hammered his cousin over the spot and his opposition to vaccines for COVID-19 and other diseases.

“My cousin’s Super Bowl ad used our uncle’s faces- and my Mother’s,” Shriver wrote. “She would be appalled by his deadly health care views. Respect for science, vaccines, & health care equity were in her DNA.”

Shriver, whose father, Sargent Shriver, founded the Peace Corps, also alluded to his own work in expanding health care access in the developing world.

Robert Kennedy Jr. responded separately to his cousin: “Bobby. I’m so sorry if that advertisement caused you pain. ... I send you and your family my sincerest apologies. God bless you.”

Kennedy is running for president as an independent despite his family’s status as Democratic Party nobility. It’s not yet clear whether he can gain ballot access in enough states to mount a true national campaign. But his effort comes in a year when many voters are not enthusiastic about the likelihood of a rematch between President Joe Biden, a Democrat, and former President Donald Trump, a Republican. Any independent or third-party efforts in battleground states could shape the outcome in unpredictable ways.

“It is fitting that the first national ad promoting Robert F. Kennedy Jr.'s candidacy was bought and paid for by Donald Trump’s largest donor this cycle,” said Democratic National Committee spokesman Alex Floyd. He was referring to Tim Mellon, a major donor to Trump who also gave American Values $15 million last year, according to federal filings.

The DNC already had filed a federal complaint alleging that Kennedy’s campaign is illegally coordinating with American Values to siphon support from Biden, an accusation the PAC denies.

A Biden campaign spokesman sidestepped the flap, instead highlighting the president’s Super Bowl Sunday debut on the social media platform TikTok.

An email newsletter from American Values framed the ad as an unqualified success, noting a spike in online searches for Kennedy and a statement from his campaign spokeswoman saying the campaign was “pleasantly surprised and grateful” for the ad, a different tone than Kennedy’s statements to his family.

At one time, Kennedy was a leading environmental activist, and he was among the younger Kennedy family members who would speak at Democratic Party conventions and events. He has in recent years delved into conspiracy theories and become a face of the anti-vaccine movement.

Besides his presidential uncle, who was assassinated in 1963, Kennedy’s political lineage includes his father, who was U.S. attorney general, a senator from New York and leading presidential candidate at the time of his 1968 assassination. His father’s longest-lived brother was Sen. Ted Kennedy of Massachusetts. Sargent Shriver, Bobby Shriver’s father, ran for president in 1976 as a Democrat.

An anti-vaccine group Kennedy led has a lawsuit pending against a number of news organizations, among them The Associated Press, accusing them of violating antitrust laws by taking action to identify misinformation, including about COVID-19 and COVID-19 vaccines. Kennedy took leave from the group when he announced his run for president but is listed as one of its attorneys in the lawsuit.