As Robert F. Kennedy Jr.’s presidential campaign begins to falter, many Democrats who had previously fretted about the scion’s once-insurgent campaign are finally hitting back in the hopes of solidifying voters around President Biden. 

The White House, Democratic strategists, members of Congress, and even members of Mr. Kennedy’s storied family have all come out to condemn his words. At the beginning of his campaign, Mr. Kennedy took nearly 20 percent of the Democratic primary vote in some polls, but new disclosures and attention paid to controversial statements have made him persona non grata in liberal circles. 

The White House first commented on Mr. Kennedy on Monday in the wake of the disclosure of a video that showed Mr. Kennedy claiming the Covid virus may have been “deliberately” targeted at whites and blacks while sparing Chinese and Jewish individuals. 

During a press conference, the White House press secretary, Karine Jean-Pierre, decried Mr. Kennedy’s comments when asked about the video by a reporter. “I want to be careful here because I don’t want to address a 2024 candidate,” Ms. Jean-Pierre said, worrying about violating the Hatch Act, which prevents government employees from discussing campaign issues. 

“But what I will say… you look at the last two, three years since 2020, since this pandemic hit, there are countless people seeing an empty seat at the Thanksgiving table because of the suffering of Covid,” she added, referencing Mr. Kennedy’s yearslong campaign against the Covid vaccine. 

“The claim made on that tape is false,” she continued, referring to the video of Mr. Kennedy discussing Covid’s disparate impact on white and blacks. “It is vile. And they put our fellow Americans in danger. If you think about the racist and antisemitic conspiracy theories that come out of saying those types of things. It’s an attack on our fellow citizens, our fellow Americans.”

The American Jewish Committee issued a statement to CNN denouncing Mr. Kennedy, who has long been involved with Jewish leaders and has been a defender of the state of Israel. 

The “assertion that Covid was genetically engineered to spare Jewish and Chinese people is deeply offensive and incredibly dangerous,” the committee wrote. “Every aspect of his comments reflect some of the most abhorrent antisemitic conspiracy theories throughout history and contributes to today’s dangerous rise of antisemitism.”

Democratic strategists have also weighed in on Mr. Kennedy’s comments. “This week was different and made sense for folks to engage because of the combination of outright antisemitism and being a witness for Republicans’ nonsense hearing,” a liberal strategist, Eddie Vale, told the Hill. 

On Thursday, Mr. Kennedy came face-to-face with many of Congress’ most influential Democrats when he sat to testify before the House Select Subcommittee on the Weaponization of the Federal Government. He was called to testify by the Republican majority about social media platforms removing some of his more controversial posts, including assertions that vaccines cause autism and his intimation that baseball legend Hank Aaron was killed by the Covid vaccine at the age of 86. 

“Free speech is not absolute,” the lead Democrat on the Weaponization Committee, Congresswoman Stacey Plaskett, said in her opening remarks. “Abusive rhetoric does not need to be promoted in the halls of the peoples’ House.”

“Even what they know about Mr. Kennedy’s hateful, evidence-free rhetoric … Speaker McCarthy and Chairman Jordan affirmatively chose to give this a platform,” Ms. Plaskett continued. “They intentionally chose to elevate this rhetoric to give these harmful, dangerous views a platform in the halls of the United States Congress.”

One of her Democratic colleagues on the committee, Congressman Gerry Connolly, took the chance to lambast Mr. Kennedy personally, saying that he was an embarrassment to his family.

“I revere your name,” Mr. Connolly said, noting that his first political hero was Mr. Kennedy’s father, Robert. “You’re not here to propound your case for censorship. You are here for cynical reasons to be used politically by that side of the aisle to embarrass the current president of the United States. And you’re an enabler in that effort today.”

“It brings shame on a storied name that I revere,” Mr. Connelly added. “I began my political interest with your father, and it makes me profoundly sad to see where we have descended today in this hearing.”

Mr. Kennedy’s own family seems to agree, somewhat, with Mr. Connolly’s assertions. One of Mr. Kennedy’s brothers, Joseph, told the Boston Globe that “his remarks in no way reflect the words and actions of our father, Robert F. Kennedy.” Another sibling, Kerry, said her brother’s remarks were “deplorable and untruthful.” 

The Special Envoy for Northern Ireland, Joe Kennedy III, who previously served as a congressman from Massachusetts and is a nephew of Mr. Kennedy, denounced his uncle’s words on Twitter. The comments were “hurtful and wrong,” the former congressman wrote, saying he “unequivocally” condemns what the current presidential candidate said about racial disparities in Covid deaths. 

President Kennedy’s grandson, Jack Schlossberg, son of Caroline Kennedy Schlossberg, in a video posted on Instagram, accusing RFK Jr. of “trading in on Camelot” and endorsing President Biden for a second term.