This article is from the archive of our partner National Journal

Senate Republicans—including a handful who are seriously considering presidential bids in 2016—could once again be forced to take a stand on immigration.

Just one week after Republican lawmakers abandoned their campaign to block funding for the Homeland Security Department unless Obama rolled back his executive actions on immigration, Sen. David Vitter is introducing an amendment on a human trafficking bill that would force senators to vote on whether they believe every baby born in the United States—even those born to undocumented immigrants—deserve to be United States citizens.

Vitter is reimagining the 14th Amendment. His bill would only give automatic citizenship to babies born in the U.S. if they have a parent who was in the military, is a lawful permanent resident, or is a U.S. citizen.

Sen. Rand Paul exemplifies the headache this is causing potential GOP candidates. He isn't exactly clear on where he stands on birthright citizenship—at least, where he stands today.

"I haven't seen it, but I'll look at it," Paul said of Vitter's amendment after leaving a Republican luncheon Thursday.

But Paul has not always been so unclear about his position on the underlying issue, or the amendment itself. In 2011, he cosponsored the amendment with Vitter. According to a press release at the time, Paul said "citizenship is a privilege, and only those who respect our immigration laws should be allowed to enjoy its benefits."

Vitter's office says the amendment today includes the same language as the amendment Paul cosponsored in 2011. When pressed further on his past involvement with the issue and whether he supported the general idea of ending birthright citizenship, Paul repeated, "I haven't seen it. I'll have to take a look at it."

Already, the once-bipartisan Justice for Victims of Trafficking Act that the amendment would be attached to is languishing in the Senate over language to block taxpayer funded abortions "except in the cases of rape, incest or life of the mother." The bill remained stuck Thursday as Democrats blocked it from moving forward after accusing Republicans of sneaking in the Hyde Amendment language. Republicans, meanwhile, have accused Democrats of sabotaging any efforts they make to productively govern.

But even if senators can get onto the trafficking bill in upcoming days, Majority Leader Mitch McConnell has promised an open amendment process. That guarantees that Republican presidential contenders would be forced into a tough vote by a member of their own party.

Paul isn't the only potential presidential candidate reticent to stake out a position on a contentious immigration amendment before it comes up for a vote in the Senate.

"Call our press office," Cruz said after being asked about where he stood on the Vitter amendment. As of press time, Cruz's office had not returned a request for comment.

Sen. Marco Rubio's office did not respond to a request about where the Florida Republican stood.

The issue of birthright citizenship is strung with traps for politicians seeking the White House. To appease the conservative base, Republicans must appear tough on illegal immigration. Voting down an amendment that would curtail so-called "birth tourism" could be seen by the right as a vote for infant amnesty. Voting for such a contentious amendment, however, could undermine a candidate's ability to make inroads with the Latino community during the general election—a constituency that the party desperately needs to appeal to if it hopes to improve upon the 27 percent of the Latino vote that Mitt Romney won in 2012.

But even Republican senators who are not aiming to be Commander in Chief fret about the toll that partisan immigration votes take on their party.

"There is a disturbing need to attach the most controversial issues to every bill we're doing," says Sen. Mark Kirk of Illinois.

Sen. Jeff Flake of Arizona, who sponsored the "gang of eight" bill in 2013 that gave some of the 11 million undocumented immigrants in the U.S. a path to citizenship, says he's constantly worried his party is backing itself into a corner it won't be able to escape.

"I will not vote for it if it comes up," Flake says. "We need to be proactively doing immigration reform, serious reform; instead ... it sends the wrong message."

Even senators who are more open to debating the merits of birthright citizenship say a human trafficking bill that has won the praise of roughly 200 outside advocacy groups is far from the best place to do it.

"I don't have a problem with the argument," says Sen. Dean Heller of Nevada. "Let's have the debate. Put it on the floor and let's have a vote on it. But I would hate to think we would kill this legislation because of a contentious amendment like this."

Sen. John Cornyn, the No. 2 Republican in the Senate and a sponsor of the trafficking legislation, says the birthright issues are "certainly extraneous to what we are trying to do here."

"We need to have that discussion in the context of the immigration debate more generally, and we will," Cornyn said.

Democrats are seizing on the amendment as an example of the GOP's failure to change its tone on immigration. Minority Leader Harry Reid called Vitter's amendment "stupid" this week (although Vitter shot back in a floor speech that Reid supported the idea more than 20 years ago) and Sen. Dick Durbin says Republicans have continued to beat the anti-immigrant drum, which will come back to haunt them in 2016.

"They believe that is the key to their election and reelection," Durbin says. "Aside from the merits of the issue, I just think they are wrong politically."

That is the ultimate call each 2016 contender in the Senate will have to make on his own if Vitter's amendment actually gets a vote on the floor.

This article is from the archive of our partner National Journal.

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