Public enthusiasm for mandatory COVID-19 vaccinations has steadily grown since the spring, with more people supporting mandatory shots to get on a plane or go back to school. Yet deep pockets of vaccine resistance held firm across the country, even as the highly contagious Delta variant has some areas reinstituting mask mandates, according to a new U.S. survey.

Overall approval for government-ordered vaccinations ticked up two percentage points to 64 percent in the early summer, according to the study by researchers from Northeastern, Harvard, Northwestern, and Rutgers. For activities such as air travel, support was even higher (70 percent in favor) compared to the last survey taken between April and May (67 percent).

While there was broad-based support across the United States for requiring vaccinations, a core group of nearly 15 percent of respondents remained either firmly opposed or highly circumspect about getting vaccinated themselves.

The stiffest opposition to mandatory inoculations came from rural residents, individuals earning less than $25,000 a year, and white people. Those most in favor lived near cities, made at least $100,000 a year, and were Asian American, according to the study.

An increase in calls for requiring vaccinations suggests that there is mounting public frustration with the unvaccinated population.

“They’re certainly connected,” says David Lazer, university distinguished professor of political science and computer sciences at Northeastern, and one of the researchers who conducted the study. “Mandates don’t directly affect the vaccinated because they’re vaccinated, but what they are doing is putting an imposition on the unvaccinated, many of whom are choosing not to be vaccinated at this point.”

Survey results could also be tied to the belief that public health campaigns have run their course, Lazer adds. After a late April surge in vaccinations by those most enthusiastic about them, “it was inevitable that the curve was going to start leveling off,” he says.

The latest poll of more than 20,000 U.S. residents was conducted nationally from early June to early July, weeks before the Centers for Disease Control and Prevention recommended on July 27 that vaccinated people resume wearing masks indoors in certain parts of the country, a reversal from earlier guidance.

The change came after new data showed that vaccinated people infected with the Delta variant could spread the virus. The CDC findings likely would not have impacted the Northeastern survey, Lazer says.

“Public opinion generally doesn’t move dramatically,” he says. Lazer predicts a wave of Delta variant cases in early September is going to “stress a lot of people out” and likely result in moving some people to get vaccinated and others to be more supportive of vaccine mandates.

President Biden has been leading federal efforts to coax the unwilling to get vaccinated, but the federal government will not mandate them, according to CDC Director Rochelle Walensky. “There will be no nationwide mandate,” she tweeted on July 30.

The nation’s nearly 2 million federal employees, however, will be asked to attest to their vaccination status. Those who do not attest or are not vaccinated will be required to wear a mask at work and get tested for SARS-CoV-2, the coronavirus that causes COVID-19.

Some states and cities have taken similar steps. California will require state employees and some health care workers to show proof of vaccination or else face mandatory weekly testing.

Other political leaders have balked at vaccine requirements.

Texas Gov. Greg Abbott has banned vaccine and mask mandates, according to an executive order. It blocks state government agencies from requiring masks or vaccine documentation for employees and also prevents private businesses from requiring masks or vaccine passports for customers.

The Northeastern survey found the highest support for vaccine mandates among residents of Massachusetts and the District of Columbia, at 81 percent each. At least 70 percent of the public in another ten states―all Democratic-leaning―approve of a universal government vaccine mandate. Support was lowest in three Republican-leaning states―North Dakota, South Dakota, and Wyoming.

The overall gap between Democrats and Republicans was the widest of any group in the survey. The chasm between the two parties did not budge between spring and summer, remaining firmly locked at a 39-percentage-point difference. Democrats overwhelmingly backed requiring vaccines while Republicans were narrowly opposed.

“It won’t surprise me if, come September, we see majorities of Republicans supporting mandates depending on how the Delta variant goes,” says Lazer.

Democrats and Republicans also differ on mandating vaccines for a return to the classroom in the fall.

Majorities in 45 states and D.C. support making vaccines mandatory for children to be allowed in school. In five Republican-leaning states—Arkansas, Wyoming, Idaho, North Dakota, and South Dakota—fewer than 50 percent of respondents were in favor, the study found.

But in Democratic-leaning areas such as Massachusetts and D.C.,over three out of four respondents supported the mandate, while two out of three respondents in mostly Northeastern states such as New York, Connecticut, and Maryland, were supportive.

The Northeastern study found high support (66 percent) among respondents for colleges and universities to require vaccinations, unchanged since April. Majorities of every demographic group surveyed except Republicans support vaccines for students as a condition of attending university in the fall.

More than 600 campuses nationally require students and employees to get vaccinated, according to a list compiled by the Chronicle of Higher Education. Northeastern was among the first to require inoculations for students, and recently announced that it would be required for faculty and staff.

For media inquiries, please contact media@northeastern.edu.