Of those surveyed, 69 percent of nonwhites, including eight in 10 Hispanics and two-thirds of blacks supported a pathway to citizenship. But only 51 percent of whites backed such a plan, leaving a difficult choice for Republican lawmakers concerned about the potential of a primary challenge.

Other provisions of immigration reform prove more popular across the board. Stricter border control earned the support of eight in 10 voters, while 72 percent backed additional visas for highly-skilled workers. Neither proposal showed a particular partisan divide, evidence of broad, bipartisan support for the measures. 

There were, however, some demographic splits on those questions. Only six in 10 Hispanics support increased border protection, far lower than any other group. Similarly, only 56 percent of blacks back an expanded program for skilled workers, despite otherwise broad support.