For context these are the questions asked since obviously this claim will change a lot based on questions. I wouldn't say it's terribly surprising based on my experiences, I've met Republicans against a lot of these things. I'm also wondering a bit how they got their sample since they had way more Democrats than Republicans and how representative it is (it also didn't close to match the racial makeup of the US). Not hating on the study, I didn't spend enough time reading it to know it's effectiveness, mainly the actual questions seemed important.

Item 1) Abortion should be illegal.

Item 2) The government should take steps to make incomes more equal.

Item 3) All unauthorized immigrants should be sent back to their home country.

Item 4) The federal budget for welfare programs should be increased.

Item 5) Lesbian, gay and trans couples should be allowed to legally marry.

Item 6) The government should regulate business to protect the environment.

Item 7) The federal government should make it more difficult to buy a gun.

Item 8) The federal government should make a concerted effort to improve social and economic conditions for African Americans.

Edit: to be clear I read the study and they used Prolific (https://www.prolific.com/) to get the participants but that means nothing to me.