A Gallup poll conducted in July 2019 showed majority support for allowing Central Americans at the United States’ southern border into the U.S. to seek asylum.
Overall, 57% of respondents favored admitting the asylum seekers, up from 51% in December 2018. Republican support for admitting the asylum seekers increased by 10 percentage points, while Independent support grew by 6 points. Regardless of political affiliation, 75% of respondents felt that the situation on the border was a crisis or a major problem needing resolution.
You can see the poll results here.