It was a battle as ferocious as one might expect in a Hudson Valley farmer’s market. This Sunday, in Rhinebeck, New York, an octogenarian backer of Robert F. Kennedy Jr. squared off against a group of local Democrats, who were there in support of Kennedy’s octogenarian rival, Joe Biden.

The Democrats had permission to set up a table at the market. The Kennedy booster, 83-year-old Frank Stoppenbach, did not, but he decided to plant himself right next to them.

“​When people came up, he talked to them about, you know, vaccines are bad, and masking is bad, and all the stuff that RFK says,” claimed Larry Cox, a member of the pro-Biden contingent. “The problem is that, being right next to us, people were thinking that he was part of us.”

The squabbling grew so bitter that Rhinebeck’s police department—an entirely part-time force—was forced to get involved to cool things down.

The dispute, previously reported by the Hudson Valley Pilot, was at once a hyper-local issue and a microcosm of agitation about Kennedy inside the Democratic Party.

Though he is running as a Democrat, Kennedy polls substantially better among Republicans, according to an analysis by FiveThirtyEight. He has alienated some liberal voters thanks to a series of controversies; most recently, several members of his own family rebuked him after he implied that Jewish and Chinese people had outsize immunity to COVID-19.

Biden’s supporters worry that Kennedy’s candidacy could tilt the general election toward the eventual GOP nominee—assuming Kennedy runs as a third-party candidate. That may explain why he is receiving millions of dollars in support from a billionaire who once backed Donald Trump, and why some members of the Republican field have praised him.

Warren Smith, chair of the Rhinebeck Democratic Committee, offered a similar take to contextualize the farmer’s market dust-up. Generally speaking, Smith said, disagreement about whom to nominate for president would be normal, but “this is kind of a different thing, because RFK Jr. has staked out a position that is on the fringes of the party.”

Stoppenbach, a registered Democrat, flatly disagreed. “Why there should be any dispute about the nomination being contested, I can’t understand,” he said.

At least some local Democrats are also on his side. Roger Quon, another member of the Rhinebeck Democratic Committee, argued that the group should “be seen as a place for all Democrats”—including Stoppenbach and Kennedy. “We can disagree with [Kennedy] on one or many points, but that’s the essence of democracy,” he said.

In Stoppenbach’s view, he was simply engaging in constitutionally protected speech to increase awareness about Kennedy and to lobby for a Democratic primary debate. He also disputed that he was antagonizing the Biden backers.

“I simply park where people come by,” he said. “I guess there may have been some people not happy with having a Kennedy appearance at the market.”

Stoppenbach, by his own account, has been politically active “for a long time, very unsuccessfully I must say.” He ran three times for county legislator, losing each time, and launched a failed bid for Congress during the 2002 election.

Stoppenbach said he was attracted to Kennedy because of their shared belief that the war in Ukraine could have been resolved diplomatically and their skepticism about the safety of coronavirus vaccines. (The Centers for Disease Control, National Institutes of Health, and World Health Organization have labeled the vaccines “safe and effective,” with “rare” adverse side effects.)

Cox suggested that Stoppenbach is overstating his reasonableness.

“We asked him to move some other place so that people wouldn't be confused, which he didn't want to do,” he recalled. Distressed, the Biden supporters put up a poster that read, “We do not support RFK.”

“We don't want to be associated in any way with RFK, Jr., and especially with his views, which we all agree are abhorrent and crazy,” Cox explained.

Echoed Smith: “Don’t try to claim the mantle of our support for your candidate.”

The anti-RFK Jr. poster blocked some of Stoppenbach’s signage, and according to Cox, “he got very agitated about that.” Eventually, cooler heads prevailed, and the easel was moved away.

Cox downplayed the disagreement. “It wasn't any sort of, as far as I know, any physical confrontation. Just an old guy with crazy ideas. Which, you know, there's no shortage of in the United States these days.”

Stoppenbach is mulling whether he’ll return to the farmer’s market next week. “I’m 83 years old, so I don’t quite have the energy I did when I was a young guy running for Congress,” he said.

“But,” he added. “You never know.”