Though it is hard to make solid predictions, a high-profile third-party run in 2024 unnerves both Republicans and Democrats who fear it might siphon off their votes. But the nervousness is especially pronounced among supporters of Joe Biden, who worry such a campaign could split the center and left and allow Donald Trump and his highly motivated rightwing base to win a return to the Oval Office.
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“Just as we organised against No Labels we’re going to organise against Robert Kennedy Jr,” Rahna Epting, executive director of MoveOn, told reporters a day after No Labels said it would not field a candidate against Biden and Trump in November.
Kennedy – an environmental attorney, conspiracy theorist and member of a famous political family – is running as an independent, gaining ballot access and polling in double figures.
“We’re going to let folks know he can’t win,” Epting said, “but he can help Trump win” by taking votes from Biden.
“We’re going to let folks know that he said he supported abortion bans. We’re going to let folks know that his vice-presidential pick [Nicole Shanahan, an attorney] calls IVF ‘one of the biggest lies’ and we’re going to let folks know that his dark money Super Pac is being funded by Trump donors.
“There’s a lot we’re gonna let folks know. This victory against No Labels is just the start. There is a lot of work that we have to do.”
No Labels said on Thursday it had not been able to find a candidate to run against Biden and Trump.
On Friday Matthew Bennett, of Third Way, said No Labels was helped on its way out by a coalition put together by his centre-left group and MoveOn, an effort “from the left all the way to the centre-right and the Never Trump movement”.
But, Bennett said, “The challenges ahead of us are in some ways even tougher.
“Kennedy cannot be talked out of this race. He is going to have a lot of money and he’s not subject to reason. So we’re going to have to make clear that voters understand who this guy is, and that is not his father.”
Kennedy is the son of the former US attorney general and New York senator Robert F Kennedy and the nephew of the 35th president, John F Kennedy.
But, Bennett said, the current Kennedy “is not a safe place to park your vote if you’re dissatisfied with something that [Biden] is doing. This guy’s dangerous and voting for him is tantamount to voting for Trump. It’s also true of the other third-party candidates, Jill Stein [the Green nominee] and anybody else who runs.”
Bennett said No Labels had posed a danger by planning to attack Biden from the political centre, even though Biden, as a Washington dealmaker of 50 years standing, was “kind of the platonic ideal of a No Labels candidate”.
Kennedy, Bennett said, “is coming from some kind of weirdo fringe … and so it is harder to understand who his coalition is. However, our view is that anyone who divides the anti-Trump coalition is dangerous.”
The Biden campaign has set up a team to combat Kennedy. But, Epting said, “It is incredibly important that we get to work in campaigning against Robert Kennedy … and ensure that the choices in November are clear to voters. It is that whether we like it or not … we live in a two-party system and there’s only two candidates that can win this presidential election. Donald Trump or Joe Biden.
“Our job is to make that very clear to voters and in terms of resources … to ensure that we re-elect President Biden and an usher in a Democratic House and Senate. We have a $32m program to do that and we will be driving … We’ve got a great team that we assigned to this No Labels work. We’re going to reassign them to our Robert Kennedy work.”
Epting and Bennett were asked what they would do to woo “the Kennedy curious”, voters who might be won back, perhaps by less brusque tactics than those employed by Hillary Clinton, who said this week anyone dissatisfied with a Biden-Trump rematch should “get over yourself”.
“We’re not going to shame people into voting for Joe Biden,” Epting said. “That is not the pathway to get us out of this quagmire.
“Really, it’s making a strategic case to voters, [saying], ‘We understand your grievances, we hear them and yet we live in a two-party presidential system.’ So the impact of your vote … will result in one of two possible worlds. A world in which Donald Trump is president, and he is dismantling our democracy even further. He is instituting a national abortion ban. He is setting up migrant camps, etc.
Related: Robert F Kennedy Jr vows to investigate January 6 prosecutions for political bias
“Or a world in which Joe Biden continues to be in the Oval Office and we’re able to continue to campaign, to push him to enact all the policies that we have dreamed up to strengthen our democracy: to go further around gun violence prevention reform, to protect abortion rights, to continue to create green new jobs and invest in our economy, to continue to tax the rich.”
Epting promised to ask “tough questions” of Kennedy on subjects such as abortion, on which he supported a 15-week ban before quickly reversing.
“We need to get [his responses] on camera and we need to share what we get … with all the voters that we can, especially in battleground states and districts,” Epting said.
Asked about previous Democratic defeats involving third-party candidates, Bennett said that as “a veteran of the [Al] Gore campaign” of 2000, “losing two elections in my professional life to third-party candidates is incredibly galling, and I have made it my mission that we won’t lose three.”
That was also a reference to 2016, when Jill Stein took votes from Clinton as Trump won.
Bennett said: “I think everybody in Democratic politics … ignored Jill Stein in 2016 because we did not think that she posed a threat, just as the Gore campaign didn’t think Ralph Nader posed a threat in 2000.
“We’re simply not going to make that mistake again.”