Byron York

On a more specific issue -- support for Obamacare -- surveys have shown that both Hispanic-American voters and Asian-American voters favor the national health care law by substantial amounts.

For Republicans, the painful results of the 2012 presidential race -- Hispanic-American voters chose Barack Obama over Mitt Romney by a 71-29 split, while Asian-American voters chose the president by a 73-26 split -- were a stark reminder that the GOP must improve its standing with those groups. But the results of the new study show why Republicans are so sharply divided over whether comprehensive immigration reform should be part of that effort.

Some advocates of comprehensive reform have been positively apocalyptic in their predictions. When Republican Sen. Lindsey Graham, a member of the Gang of Eight, was asked last June about the GOP's 2016 presidential field, he responded, "If we don't pass immigration reform, if we don't get it off the table in a reasonable, practical way, it doesn't matter who you run in 2016. We're in a demographic death spiral as a party, and the only way we can get back in good graces with the Hispanic community, in my view, is pass comprehensive immigration reform."

For others, the new study suggests that Graham's prescription will make the Republican challenge infinitely more difficult. "It is difficult to see how Republicans remain both a small-government-oriented party and competitive in the face of the electorate that legal immigration is creating," says Camarota.

The GOP faces a hard enough job improving its standing among the 15 million new potential immigrant voters who will be here if nothing is changed in the law. Adding another 17 million through comprehensive immigration reform would steepen the hill considerably. When Republicans debate the politics of reform, those are numbers they should remember.

Byron York

Byron York, chief political correspondent for The Washington Examiner