Not everyone's jumping on board the Trump trend of rejecting 'birthright citizenship.' REUTERS/Brian Snyder

MOBILE, Ala. -- Donald Trump's ambitious, deportation-centric immigration plan has resonated in southern Alabama, where a rally tonight has already attracted more than 35,000 RSVPs. Trump's rejection of "birthright citizenship" and embrace of the term "anchor babies" have caught on, too. Sen. Ted Cruz (R-Tex.) and Gov. Bobby Jindal (R-La.), both of whom see potential in the coming "SEC primary" of Southern states -- and have parents born outside the United States -- have backed Trump's position. In conversations, conservative voters near Mobile have praised Trump's rejection of "political correctness" and his forthrightness on a key issue.

"The people of south Alabama don’t want illegal immigrants flowing across our border and not being sent back where they came from," said Dean Young, a conservative activist who nearly won Mobile's congressional seat in a 2012 special election. "It doesn’t make sense for someone to have a baby in this country and use that to live here for life."

Yet for some conservative commentators, increasingly fed up with Trump, the birthright issue has become a way to argue about what the Republican Party stands for. The Federalist, the young conservative opinion site founded by Ben Domenech, is leading the day with his essay about how Trump's campaign risks turning the GOP into a party of "white identity politics." (The illustration is from Bioshock: Infinite, a game set on a floating city founded by white supremacists.) Elsewhere on the site, Robert Tracinski argues that there is "nothing more conservative" than the idea that people born in America are ineffably American.

"For the Founders," writes Tracinski, "rejecting jus soli or birthright citizenship would have meant either greatly restricting the growth and expansion of the new nation or, more likely, creating a system in which there was a large and growing sub-population of people who were disenfranchised in the land of their own birth—an idea totally incompatible with a government based on the consent of the governed."

At National Review, Roger Clegg has pointed readers to his omnibus argument in favor of birthright citizenship and the broad interpretation of the Fourteenth Amendment.

"The term 'anchor baby,' which is often used to describe the citizen children of illegal immigrants, suggests that such births make it harder to deport illegal aliens, and thus also make it more attractive for them to sneak into the country," he writes. "If that were true then that might indeed be a problem (though whether it is a big enough problem to justify changing the Constitution would be another question). But the premise is false. According to a study by the Department of Homeland Security, over the last ten years, 100,000 parents of U.S. citizen children have been deported, nearly 5 percent of the total number of deportees during that time period."

That's still Clegg's opinion, but the essay is a little out of date. The current birthright debate is fueled not just by theory, but by President Obama's 2012 and 2014 actions to defer deportation for children brought to the United States as children, and for the parents of children born in the United States. So far only one Republican presidential candidate has pushed through that context and come out defending birthright citizenship.

"The guarantees of the Fourteenth Amendment to the U.S. Constitution are emphatic,” former Virginia Governor Jim Gilmore said in a Fox News interview. “To begin to talk about a government pick and choose who gets citizenship and who doesn’t, to pick a favored class, is wrong.”

Gilmore, the last Republican candidate to enter the race, has yet to reach single-digit support in any poll.