Just two years after Robert F. Kennedy Jr. and his “Make America Healthy Again” movement helped propel President Donald Trump into the White House, the now-Secretary of Health and Human Services is highlighting a political vulnerability in a bellwether state.

A measles outbreak in Pennsylvania has made public health a sharp issue of attack against the Trump administration, joining the cost of living and the war in Iran as a chief concern among voters that Democrats have seized upon.

And across the country — including in states that have seen hundreds of measles cases this year — Democratic candidates have sought to convert growing distrust for Republicans on public health into political advantage. The biggest outbreaks have centered in deeply red districts in places like Wisconsin, Utah and South Carolina – a state that could elect a Democratic senator who has said she ran in part to push back against Kennedy.

Some see an opportunity to highlight the chaos sown by federal changes to vaccine policy and Americans’ divided views on the health secretary, who espouses skepticism about vaccine safety and has denied that falling immunization rates have led to the rapid spread of infections.

More registered voters trust Democrats than Republicans – 41% compared to 25% — to handle vaccine policy, according to a May KFF poll. Sixty percent of voters said they disapproved of Kennedy’s performance as HHS secretary.

“What we’ve seen is that voters are really turned off by RFK Jr.’s unscientific approach to public health,” said Shaughnessy Naughton, a former Democratic Pennsylvania congressional candidate who founded 314 Action, a political strategy group that funds Democratic candidates with scientific backgrounds.

314 Action has run a six-figure ad campaign in at least five states — including Pennsylvania — expressly linking Republicans in competitive races with Kennedy Jr and unpopular federal policies.

The campaign started in April as measles began spreading in Pennsylvania, where the group is targeting Pennsylvania’s 7th Congressional District, which Republicans narrowly flipped in 2024.

Even some Republicans see eroding trust for the party as it relates to science as a problem. “There’s certainly no shortage of tight election races. Anytime you have a tight race, who knows what’s going to trip the balance for a particular voter?” said Michael Burgess, a former Texas GOP congressman and doctor. “Why take a chance on alienating a potential supporter?” he asked, referring to the messaging on vaccines.

A Reuters/Ipsos survey conducted in September that interviewed 896 registered voters nationwide showed that 62% were concerned about measles outbreaks and 55% said they disapproved of how Trump was handling the outbreaks in parts of the US. For Democrats and their backers, RFK Jr. is seen as the central figure of blame.

“The more that people are reminded of what he’s actually said and done, and the fact that the Republicans have done nothing to try to hold him accountable, I think that does resonate with voters,” said Naughton. HHS did not respond to a request for comment.

In Pennsylvania, which has seen more than 1,300 cases and five deaths from measles this year, the ongoing health crisis has threaded together Democratic governor Josh Shapiro’s public battles with the Trump administration and his bid to win reelection this November.

Shapiro has openly sparred with federal health officials after Kennedy, in an extraordinary move this summer, questioned whether people had died from the disease and suggested Shapiro’s staff was “fear-mongering” about the severity of its spread.

The feud has frustrated even some Kennedy supporters in the state. A midwife serving measles-stricken communities in the state told CNN that Kennedy “is denying the science” and “has misrepresented the numbers.”“All that does is create more confusion,” said the midwife, who reported seeing measles cases every day in recent weeks. She asked not to be named, citing concerns about patient privacy.

The debate has forced Shapiro’s opponent, state treasurer Stacy Garrity, to reassure voters that she supports vaccines and distance herself from Kennedy, with whom she appeared at a “Make America Healthy Again” rally in Harrisburg — a fact moderators pointed out at a debate this month.

It was the only MAHA event Kennedy has done in Pennsylvania since measles began to spread.

“That was in support of basically healthy eating for our kids,” Garrity said. “But I’m fully vaccinated. I believe in vaccinations.”

Down ballot, 314 Action’s ads home in on a competitive Pennsylvanian district by claiming that the incumbent GOP Rep. Ryan Mackenzie “won’t stand up to Trump and RFK Jr.” The Cook Political Report currently rates the district as a leaning Democrat.

A statewide poll from Franklin and Marshall College this month found that 70% of voters believe the state should be doing more to encourage vaccination. Most Democrats aligned with that belief, as did most independent voters and nearly half — 49% — of Republican voters.

“It’s not the pivotal issue for voters as they weigh rising cost of living and foreign wars, but it’s another on the list of unpopular policies that Republican candidate have to contend with,” said Berwood Yost, the director of the college’s Center for Opinion Research who led the poll.

Voters are “really thinking about Trump and the Trump administration,” he said. “Kennedy’s part of that; he’s part of those policy pronouncements that people might be judging.”Anthony Kotsagrelos lives with his wife in the Pittsburgh area, where they got their one-year-old son vaccinated for measles last month.

Kotsagrelos, a pediatric medical assistant, told CNN he has seen a “dramatic increase” in vaccine skepticism firsthand since the 2024 election and RFK Jr.’s appointment as HHS Secretary.

“I have some doctors at my job who have been in practice in pediatrics going on 50 years, and they’ve said that this is the worst it’s ever been with vaccine hesitancy, with misinformation,” he said.

He has written letters to RFK Jr. explaining that his vaccine rhetoric has caused “unnecessary deaths” and “unnecessary stress” for parents.

That is translating into political change for people around him, Kotsagrelos said. People in his work and social circles who would have otherwise voted Republican are now leaning left, citing reasons like the return of measles as well as higher gas prices and economic downturn.

“They’ll kind of say like, ‘Well I’ll vote for whoever would keep my kids safe now,’ and that switched from people being against the Democratic Party,” he said.

A measles outbreak in South Carolina this past year “was definitely one of the main talking points among several subgroups of Annie Andrews supporters” during the primaries, said Scott Huffmon, executive director of Winthrop University’s Center for Public Opinion and Policy Research.

Although it has since dropped off the list of top issues in the Senate race, Andrews, the Democratic nominee and a pediatrician, has said that she was motivated to run for office by Kennedy’s confirmation to lead HHS, arguing that his public messaging and anti-vaccine advocacy eroded public trust in health institutions.

In Spartanburg County last month, Andrews drew applause when she said she’d push to impeach Kennedy if elected. Kennedy has not made any trips to South Carolina since the start of the measles outbreak there last October.

A New York Times/Siena poll puts Andrews in a dead heat with Republican Sen. Darline Graham at 48% among likely voters, making for an unexpectedly competitive race in the deeply red state. Graham was recently appointed to her seat after the death of her brother, Lindsey Graham.

Kathryn Harvey, the Democratic Party chair for Spartanburg County, the epicenter of the state’s measles outbreak that saw 940 cases, said that while it still comes up during town halls and panels Andrews has participated in, other issues have pushed their way to the forefront for voters since the area’s outbreak was declared over in April.

“I think for Annie as a candidate, it’s still top of mind because the outbreak happened on the heels of RFK’s leadership, and we’re just seeing that trickle down happen in our community and it’s also very much a product of the passing of our statehouse laws that relaxed the immunization in our schools,” Harvey said. “It’s just a matter of, is it making the top three issues across the state? And I would say the answer is no, just by proxy of where we are with gas prices and kind of the overarching Republican corruption.”

Besides Andrews, an unprecedented number of doctors and scientists are running for office up and down the ballot this year, noted Naughton. Ohio gubernatorial candidate Amy Acton and Michigan Senate candidate Abdul El-Sayed — both doctors — have pointed to Kennedy when attacking the administration and Republicans on health.

This month, Burgess and another former Republican congressmen and doctor, Larry Bucshon of Indiana, warn in Stat News, a medical news outlet, that “silence on vaccines is becoming a dealbreaker for voters who would otherwise vote Republican” and that “Democratic candidates have wasted no time in turning the issue to their advantage.”Yet RFK Jr.’s vaccine skepticism rhetoric resonates in some conservative communities that prioritize medical freedom, especially for religious reasons. Those can be tricky waters for Democrats to navigate.

Though more than 700 measles cases have been recorded in Utah since June 2025, a vein of support for medical freedom makes blaming the outbreak on MAHA-fanned vaccine skepticism a harder sell.

“There is a ton of this kind of self-determination autonomy, like, ‘I will decide, the government won’t decide,’ in this state,” said Democratic state Sen. Jen Plumb, who also works as an emergency room pediatrician and is running for reelection.

“I know I will alienate those people if I fully share with them why I care so much about vaccines because I will make it seem, whether I want to or not, like they don’t care as much about their kids,” she said. “That’s not going to help their kids or help me help them.”