Around 70 percent of Americans have received at least one shot of the coronavirus vaccine, which suggests that the United States is close to so-called herd immunity.However, the rapid spread of the highly-contagious Delta variant -- which can, though rarely, evade antibodies from vaccines and infections -- has been a major source of concern.Policymakers and public health officials have used numerous strategies to convince the vaccine hesitant to get their shots; pleaded with them, shamed them and even "bribed" them.A new study sheds some light on this phenomenon.Read More BelowResearchers from Carnegie Mellon University and the University of Pittsburgh analyzed more than five million poll responses to determine how vaccine hesitant different demographic groups are.Participants were categorized as vaccine hesitant if they answered that they "probably" or "definitely" would not get vaccinated against COVID-19.Some findings confirmed conventional wisdom. For example, the researchers found that supporters of former President Donald Trump -- people who voted for him in the 2020 election -- were more likely to say they don't want to get vaccinated.Other findings were quite shocking, according to UnHerd.Shocking FindingsThe researchers also analyzed and broke down the data by level of education, finding that vaccine hesitancy is high among least educated and most educated.The highest vaccine hesitancy was among respondents holding a Ph.D, while the lowest hesitancy was among people with a master's degree.In other words, "the association between hesitancy and education level follows a U-shaped curve with the highest hesitancy among those least and most educated."The study also found that the highly educated are unlikely to change their minds about taking the vaccine.Racial DisparitiesOther studies suggest that there are also some racial disparities.The Kaiser Family Foundation has found that Black and Hispanic people remain less likely than white people to have received a COVID-19 vaccine."As observed in prior weeks, Black and Hispanic people have received smaller shares of vaccinations compared to their shares of cases and compared to their shares of the total population in most states," the foundation noted earlier this month."Reaching high vaccination rates across individuals and communities will be key for achieving broad protection through a vaccine, mitigating the disproportionate impacts of the virus for people of color, and preventing widening racial health disparities going forward."PollsPolling paints a similar picture.In a Monmouth University poll released earlier this month, a majority of respondents overall said they were concerned about coronavirus and expressed support for mask mandates and other similar measures.Forty-eight percent of respondents in the survey said they were at least somewhat concerned about contracting coronavirus, while 53 percent said they were concerned a family member would get it.However, the vaccinated were more concerned about the virus than the vaccine hesitant. Just 16 percent of the vaccine hesitant in the poll said they were concerned about being infected with COVID-19.