RFK Jr.’s Threat to Trump

November’s election may be decided by whose definition of Robert F. Kennedy Jr.

voters find most persuasive.

No one really knows which of his rivals Mr. Kennedy’s candidacy will hurt more. Mr. Biden sees Mr. Kennedy as possibly reprising the role played by the Green Party’s Jill Stein in 2016. Her vote totals were slim—in Pennsylvania she received 0.82%, in Michigan 1.07%, in Wisconsin 1.04%—but had her votes gone instead to Hillary Clinton, Mr. Trump wouldn’t have been president.

With Mr. Kennedy polling today in the low double digits, Mr. Biden is taking no chances. He has gathered endorsements from almost the entire Kennedy family and even set up a war room to track the RFK campaign and make it harder for him to get on state ballots. Team Biden is trying to portray Mr. Kennedy as a creature of MAGA, citing his antivax stands and his financial support from Trump donor Timothy Mellon.

Mr. Trump is smart to hammer Mr. Kennedy on the issues and cast him as further to the left than Mr. Biden. For one thing, it clarifies things for Republican and independent voters who might buy the nonsense that Mr. Kennedy is conservative. For another, the more vehement Mr. Trump’s attacks on Mr.

Kennedy are, the more the former president increases RFK Jr.’s attractiveness to Democrats already disenchanted with the president.

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