Democrats are sounding the alarm over Green Party candidate Jill Stein as they look to avoid a repeat of the 2016 presidential election, in which Stein was accused of playing spoiler in key swing states.

For months, Democrats had trained their ire on Robert F. Kennedy Jr.’s independent campaign for the White House, and largely dismissed the impact Stein or other third-party aspirants could have in the battle between Vice President Harris and former President Trump.

Now, with Kennedy out of the race and less than three weeks to go before Election Day, the party is warning that Stein could once again have a damaging effect in a match-up where every vote in the swing states will matter.

“The threat from Jill Stein’s candidacy is real and growing by the day,” said Doug Gordon, a Democratic election operative and co-founder of UpShift Strategies. “Stein was instrumental to Trump getting a first term and she could be key to giving him a second term.”

National Democrats’ anti-third-party crusade was at its peak when President Biden was trailing Trump and Kennedy was seeking to get on every state ballot. After he dropped out, the third-party threat seemed to fade, with more marginal candidates such as Stein and fellow leftist Cornel West becoming afterthoughts.

Kennedy, who has become a top surrogate for Trump since dropping out, posed a specific threat to Democrats in that he had a famous name attached to their party but aligned politically with the right on many issues. Stein, however, is to the left of most progressives and, in Democrats’ estimation, comes with her own unique baggage.

That lingering, eight-year-old resentment has prompted an uptick of activity across the party, with Harris’s allies strategizing multiple ways to cut off any support she has in states where 1 and 2 percent support could be decisive.

“The small number of votes she won in 2016 in key battleground states was the difference between Clinton winning and Trump winning,” Gordon warned. “And with this race looking even closer than 2016, the votes that Stein gets will play an even greater role in helping Trump.”

The Democratic National Committee (DNC) is reinvigorating its opposition effort against Stein, tailoring its messaging in battlegrounds to warn voters that she could cost Harris the election. Party officials have launched a series of billboards in Wisconsin and Arizona calling the physician candidate a “spoiler.”

One ad, which is currently overlooking West Glendale Avenue in Phoenix, depicts a mock-up image of Stein wearing Trump’s signature red “Make America Great Again” hat. While the former president hasn’t paid too much attention to Stein on the campaign trail, he has briefly lauded her ability to pull support from Democrats.

Organizers with the DNC and liberal groups feel increased anxiety this cycle and are working in tandem to remind voters that Trump’s ascent to the White House was made possible partly by Stein.

“We’re not leaving anything up to chance and will do whatever it takes to remind Arizona voters Jill Stein is a spoiler candidate who can help send Donald Trump back to the White House. Don’t leave it up to chance,” the DNC’s messaging reads. “The only way to avoid a repeat of 2016 is to cast your vote for Kamala Harris.” The Grand Canyon state ad was “authorized” by Harris’s campaign.

Stein is expected to appear on a dozen state ballots, including safe blue California and New Jersey, Republican strongholds Louisiana and West Virginia and GOP-leaning states Florida and Texas. But the majority of states where she’ll compete are the closest watched battlegrounds, including Arizona, Georgia, Pennsylvania, Michigan and Wisconsin.

Trump’s path to 270 electoral votes doesn’t hinge on those three states as much as Harris’s does, but both candidates are intensely targeting Pennsylvania, which went for Trump in 2016 and swung back for Biden as his home state in 2020.

A recent poll shows Stein occupying 1 percent of support in the Keystone State, according to a survey with The New York Times/Philadelphia Inquirer and Siena College. Libertarian candidate Chase Oliver held a slightly lower showing of support among voters surveyed, but analysts widely agree that 1 percent — and even as little as a half of 1 percent — is enough to make a difference in the states with the tightest margins.

In Wisconsin, another battleground where the DNC has spent resources to attack Stein, the state Supreme Court shot down an appeal to remove her from the ballot before voters go to the polls. Stein is joined on the Badger State ballot by West, Oliver and even Kennedy, who has encouraged his supporters to vote for Trump but could nonetheless siphon off unknown avenues for support due to his efforts to be removed from the ballot being rejected.

While some Democrats see Stein as politically irrelevant, and even go as far as to call her multiple long-shot bids as desperate attempts to get attention, others paint a more alarmist view of her campaign, especially as many expect this race to be even closer than 2020’s. Those who hold that posture argue that Stein’s very presence in the White House contest represents a threat to democracy by proxy.

“She’s funded, supported and co-opted by extremist Trump MAGA loyalists who know she cannot win but that she only serves to make it easier for Trump to win,” said Joel Payne, chief communications officer for MoveOn, which along with the DNC has led the effort to squash third parties.

“That’s why so many of us who are fighting to keep Trump away from the White House are doing the work to call out Jill Stein, her MAGA backers and her extremist ideas like defending white supremacists and Jan. 6 insurrectionists,” Payne said.

Stein’s ideology couldn’t be further from Republicans, but, like others in the third-party lane, including Kennedy prior to his departure, she has gotten a boost from controversial GOP figures who want to see her help defeat Harris in the final weeks. This week, former KKK grand wizard David Duke offered Stein his support in a move that was widely perceived as a bid to prop up Trump.

“A racist troll has ‘endorsed’ our campaign to draw attention to himself, and certain smear merchants are happy to platform this troll to attack us,” Stein wrote on the social platform X, denouncing Duke and flipping the script back to Harris for what she considers her unacceptable endorsement from former Republican Vice President Dick Cheney.

Establishment Democrats have more help this year than in 2016 from young voters, a portion of whom voted for Stein as a protest against Clinton over differences in foreign policy and war. Generation Z voters, who at this point are largely rallying behind Harris, are aware of their age bracket’s history of voting against the two-party system and have formed a group called “Voters of Tomorrow” to help blunt Stein’s momentum among the youth. On TikTok, the group’s hosts called Stein a “scammer,” seeking to reach their demographic who lives on social media.

Most of Democrats’ renewed focus has been on Stein, but some are also warning about West, whose swing-state tally includes Wisconsin, Nevada and North Carolina after recently losing court cases to compete in Pennsylvania and Georgia.

North Carolina, where West won his lawsuit to appear on the ballot, has become a bigger electoral unknown as Hurricane Helene has upended the voting process.

Harris is currently only slightly ahead of Trump in the Tar Heel State. In the latest Quinnipiac University survey released Wednesday, she leads the former president 49 percent to 47 percent. In total, third-party candidates in the state earn 4 percent of support — with West and Stein each occupying 1 percent, and 2 percent backing Oliver.

Cynthia Wallace, executive director of the New Rural Project in North Carolina, noted that while there have been “a lot of lawsuits” among third–party candidates vying to play in the state, the focus of the electorate remains on Trump and Harris.

And as is true in any cycle, an intriguing — or worrisome — polling presence doesn’t necessarily mean actual votes cast.

“I’ve not heard any conversation in my travels in our rural counties or on the doors about anyone other than Kamala Harris and Donald Trump,” Wallace said.