When liberal pro-immigration groups criticize a Republican candidate, it will often understandably be written off as pure partisanship (or in some cases, preparing for a plum administration appointment). But what happens when the presumptive GOP nominee is taking fire on immigration from Republican groups, and even a Republican governor who has attracted speculation she might be considered for the vice presidential nomination? The Wall Street Journal reports:

Mitt Romney’s embrace of Kris Kobach, the man behind a spate of laws intended to rid states like Arizona of illegal immigrants, is drawing fire from Hispanic Republicans and immigrant advocates who say the GOP front-runner has damaged his chances of attracting Latino voters in the presidential election.

“Romney committed political suicide when he received Kobach’s endorsement,” said DeeDee Garcia Blase, founder of Somos Republicans, a grassroots Latino Republican group. Somos Republicans announced Monday that it is endorsing Newt Gingrich in the Republican primary.

[…]

Concerned about alienating Hispanics, the Republican National Committee has enlisted a director for Latino outreach. New Mexico Gov. Susan Martinez, who is a Republican, last week urged her party’s presidential candidates to tone down their immigration rhetoric. Arizona Sen. John McCain is also among prominent Republicans who have recently cautioned against taking an anti-immigrant stance.

Romney has chosen immigration as one area to run to the right of his rivals to shore up his conservative credibility. But it may not have been the best choice. The issue has potency, and in fact hurt Rick Perry’s candidacy a few months ago when he defended, somewhat awkwardly, offering in-state tuition to the children of illegal immigrants. Newt Gingrich also took a more moderate line on immigration, similar to Perry’s, and it seemed to leave him unscathed.

But as a general-election issue, Romney may have put himself in a box. Romney is not just to the right of Gingrich and Perry on the issue; he’s to the right of every Republican presidential nominee in recent history. After Ann Coulter and Peter Robinson discussed the topic on a Ricochet podcast last week, Ben Domenech jumped into the fray with some statistics that reveal why the GOP’s border state politicians are telling Romney to cool it:

Now, I’m skeptical of a lot of data about illegal immigrants because, well, it’s a bit difficult to assess. But as far as such data goes, the folks at Pew do a pretty thorough job. They estimated recently that two-thirds of illegal immigrants have been here for more than a decade.

Of the total, Pew found that 35% of illegal immigrants have been here for more than 15 years. And only 15% have been here for less than five years (this is the area where I think their estimate is questionable, as that would likely be the population more difficult to track; on the flip side, the economic downturn of the last four years has almost certainly slowed traffic in this direction).

The overall point is that a long-term illegal immigrant is not some outlier, but actually a significant portion of the population.

If you support hard-line policies to curb illegal immigration, at some point you have to ask yourself whether your plan really calls for the deportation of 6.4 million adults (out of the 10.2 estimated total) who have been in this country for at least a decade, almost half of whom have children under the age of 18. If the answer is yes, you are left with two follow-up questions: Can this in any way be considered realistic? And presuming you do not accomplish this (for a host of reasons), have you just told 3 million parents in the demographic that accounted for 56 percent of the nation’s population growth in the last decade that your party wants them and their children out?

In other words, is it possible your plan is both bad politics and bad policy? Since the general-election ads against this line have presumably already been cut, Romney needs to have answers to all those questions.