Bernie Sanders and Hillary Clinton took of the gloves and duked it out over immigration reform and other issues during Thursday night’s PBS/Facebook debate. Sec. Clinton and Sen. Sanders agree on a number of immigration issues. They both support Barack Obama’s executive actions to give around 5 million immigrants in the country illegally reprieve from deportation. They both have pledged to pursue comprehensive immigration reform. They both reject  a an Obama administration policy that lets vulnerable immigrants face hearings without a lawyer. However the Democratic primary candidates disagree on the role of immigration enforcement and which compromises might be necessary to pass a comprehensive reform bill.

Clinton attacked Sander’s record, pointing to a 2007 vote against a Bush-era immigration reform bill. The exchange exposes a fundamental tension between the candidate’s beliefs. In particular, Sanders has said that immigrants, guest workers in particular, drive down wages.

(These uncorrected rush quotes are taken from the Washington Post’s annotated transcript.)

1) Guest Workers: A Deal-Breaker For Comprehensive Immigration Reform?

“I'm a strong supporter of comprehensive immigration reform,” Clinton said. “Have been ever since I was in the Senate. I was one of the original sponsors of the DREAM Act. I voted for comprehensive immigration reform in 2007. Senator Sanders voted against it at that time.”

Both candidates support permanent residency and citizenship for the estimated 10.9 million immigrants in the country illegally, but Clinton has voted for a measure allow more guest workers, and Sanders has opposed it. Sanders doubled down on his vote, citing liberal groups who opposed the bill, including LULAC and the SPLC.

“In terms of 2007 immigration reform, yeah, I did vote against it,” Sanders said. “I voted against it because the Southern Poverty Law Center, among other groups, said that the guest-worker programs that were embedded in this agreement were ‘akin to slavery.’”

Clinton answered later in the debate with a counter attack.

“[With] respect to the 2007 bill,” she said “this was Ted Kennedy's bill. And I think Ted Kennedy had a very clear idea about what needed to be done. And I was proud to stand with him and support it.”

2) Deport Unaccompanied Central American Migrant Minors?

Sanders in turn attacked Clinton on Obama-era deportation policies executed while she was serving as Sec. of State. Specifically, he attacked Hillary Clinton’s comments that unaccompanied minors fleeing violence in Central America should be “sent back.”

“Secretary Clinton, I do have a disagreement here,” Sanders said. “If my memory is correct, I think when we saw children coming from these horrendous, horrendously violent areas of Honduras and neighboring countries, people who are fleeing drug violence and cartel violence, I thought it was a good idea to allow those children to stay in this country.”

In kind, Clinton doubled down on her defense of the Obama administration policy uses deportations and enforcement to deter future migration.  

“[With] respect to the Central American children,” Clinton said, “I made it very clear that those children needed to be processed appropriately, but we also had to send a message to families and communities in Central America not to send their children on this dangerous journey in the hands of smugglers.”

Sanders and Clinton on fought it out on other issues as well, with bare-knuckle exchanges on their healthcare plans as well as their view of the Obama legacy. Clinton scored points hitting Sanders on his vague universal health care proposal. Sanders hit back against clinton on foreign policy, probably for the first time in the campaign, by attacking Clinton’s admiration of Henry Kissinger (a pariah in progressive foreign policy).

Sander’s biggest punch of the night, however, might have come during the crescendo of the immigration section when he got the last word in on the Central American minors by throwing Clinton’s words back in her face.

“Who are you sending a message to?” he asked, rhetorically. “These are children who are leaving countries and neighborhoods where their lives are at stake. That was the fact. I don't think we use them to send a message. I think we welcome them into this country and do the best we can to help them get their lives together.”

It is no mistake that immigration reform was a top issue in Thursday’s debate. PBS moderators cited the upcoming Feb. 20 Nevada caucus when introducing the issue. Candidates have had field organizers working Nevada Latino communities for months. It is the first early state with a significant Hispanic population, but it will not be the last.

What will have a greater impact on voters: Hillary’s support of deportations or Sander’s vote against immigration reform? Let us know your thoughts in the comments below.