Updated 3:50pm Tuesday, July 18.

As Senator Manchin teases Democrats by flirting with the idea of a third-party presidential bid via the nonpartisan group No Labels, other nonpartisan and bipartisan groups are launching campaigns to discredit the group, fearing that it could hand the election to President Trump should it put forward a third-party candidate.

Mr. Manchin, a conservative Democrat who No Labels has been attempting to recruit for a third-party presidential bid in 2024, attended the rollout of the group’s platform at an event at Saint Anselm College in New Hampshire on Monday.

“The business of politics is big business,” Mr. Manchin told reporters. “The politics in Washington is a better business model if they can keep you divided. We’re trying to say: ‘Hey boys, get off your high horse on the right and the left and come back together and let’s do our job.’”

At the same time, Mr. Manchin reiterated a promise not to play the spoiler in 2024. Most polls, though, show a vigorous third-party bid from Mr. Manchin would likely deliver the presidency to Mr. Trump, the likely GOP nominee.

“I’ve never been in any race to spoil. I get into races to win. And if I get in the race, I’m going to win,” Mr. Manchin said at the event. “With that being said, I haven’t made a decision.”

Despite the open question of whether Mr. Manchin will run and the qualifications No Labels has put on its efforts — it has said it won’t put up a candidate if President Biden has a significant lead in the polls by Super Tuesday — the backlash against the group is spreading. 

Another bipartisan group, Citizens to Save Our Republic, has launched with the express purpose of attacking No Labels and preventing it from helping Mr. Trump win the 2024 election.

A longtime Republican strategist now serving as a spokesman at Citizens to Save Our Republic, Stuart Stevens, tells the Sun that what No Labels is saying “makes no sense.”

“I have friends over there who can’t name a single state they think they can win,” Mr. Stevens says. “The question here that is so perplexing is when smart people are saying something that is stupid, why are they saying it?”

Mr. Stevens raised questions about some of No Labels’s criticisms of Mr. Biden, such as theiargument that Mr. Biden is too old, even though Mr. Manchin himself turns 76 next month. He also pointed out that No Labels says it’s trying to give Americans more choices but isn’t holding a primary.

“I spent 30 years pointing out flaws in the Democratic Party and was pretty good at it,” Mr. Stevens said. “None of this matters anymore. They’re the only pro-democracy party in America.”

A representative of No Labels, chief strategist Ryan Clancy, responded to some of this criticism, telling the Sun, “This is a group of Washington insiders conspiring to deny America’s constitutional right to choose which candidates appear on voting ballots.”

“They apparently believe we should suspend democracy and clear the way for Joe Biden and Donald Trump to attack each other for the next year,” Mr. Clancy says. “Most Americans don’t agree.”

Mr. Clancy reiterated that No Labels’s stance is that it is aiming to provide “more voices in our politics” by “working to get ballot access nationwide.”

In response to this claim, Mr. Stevens called on No Labels to release a list of its donors and suggested that, in his opinion, there could be considerable overlap between the people supporting No Labels and those supporting the presidential campaign of attorney Robert Kennedy Jr., who’s seeking the Democratic nomination.

“Why won’t they release their donors? Most campaigns are proud of their donors,” Mr. Stevens says. “Why is it that there’s a bunch of people supporting No Labels that don’t want to be associated with No Labels?”

Mr. Clancy responded, saying that No Labels is not required to disclose donors and is “not going to provide a list that others can use to harass our supporters.”

“Yesterday, Dick Gephardt said one of the explicit aims of his new group is to pressure No Labels donors to abandon us,” Mr. Clancy said. “We’re a 501c4 group engaged in voter registration and ballot access.”

Other groups have responded to No Labels’s platform, which was rolled out on Monday. One liberal centrist group, Third Way, published an attack on No Labels and its ostensibly nonpartisan brand. 

Third Way accused No Labels of sidestepping the most prominent issues dividing Democratic and Republican voters in America, saying, “This timid and vague policy plan dodges hard choices to move the country forward and openly evades many crucial issues.”

Third Way called out the 72-page No Labels platform for laying out mostly unobjectionable goals but skimping on specifics on issues like the national debt, government spending, the climate, cultural issues, national security, and election security.

Other groups like the Lincoln Democracy Institute, which was formed in opposition to Mr. Trump and his brand of politics, have released an ad accusing No Labels of being a project with the goal of electing Mr. Trump. 

“Their own internal polling shows that (their) efforts will produce a second term for Donald Trump,” the speaker in the ad says. “But this is nothing new for No Labels. They’ve been running cover for corrupt politicians for years.”

The ad splices clips of Mr. Trump praising No Labels, saying, “I’m a believer,” with newspaper clippings describing the organization’s relationship with billionaire Harlan Crow. 

“They’ve staffed up with people from Trump’s corrupt administration and their own internal polling shows that the efforts will produce a second term for Donald Trump,” the ad says.