Last week was supposed to be a pivotal moment for an immigration deal. But despite days of debate and numerous proposals, senators were not able to pass a concrete immigration solution.

Four separate immigration measures failed in the Senate.

Part of the conundrum is that President Trump seems unwilling to sign any bill that does not include a commitment to narrowing legal immigration, after originally saying he would pass any bill that lawmakers could agree on.

If Congress does not come up with a solution soon, and the courts don't offer some clarity, some 700,000 people protected from deportation under the Deferred Action for Childhood Arrivals program (DACA) could lose their status.

Assumption versus reality

Immigration appears thoroughly ingrained in the Democratic brand. When the center-left think tank Third Way conducted surveys after the 2016 election with voters, nearly all of them pointed to the same thing.

"When we asked people what Democrats stood for, immigration was one of the biggest words that came up in the word cloud that people used to discuss Democrats," said Lanae Erickson Hatalsky, vice president for social policy and politics at Third Way. "[Immigration] was a mainstay of how people saw the Democratic Party."

And so the logical conclusion ahead of the 2016 presidential election was that Trump's unfriendly immigration rhetoric would help Democrats.

"One of the things that many analysts had pointed to is Donald Trump's comments about immigrants, particularly Mexican immigrants, might motivate Latino voters to turn out in record numbers," explained Mark Hugo Lopez, the director of Hispanic Research at the Pew Research Center.

That did not exactly happen. For one thing, the top issue for Latino voters — like all voters — was the economy. And the Latino turnout rate actually declined compared from 48 percent in 2012 to 47.6 percent in 2016.

Despite the assumption that immigration is a pillar of the Democratic Party, in the last presidential election, it galvanized Republicans far more than Democrats.

Trump voters

President Trump made immigration the backbone of his campaign.

"When Mexico sends its people, they're not sending their best," Trump said at his 2015 campaign announcement. "They're sending people that have lots of problems, and they're bringing those problems with us. They're bringing drugs. They're bringing crime. They're rapists. And some, I assume, are good people."

Trump successfully moved immigration into the core of the Republican Party's identity.

In the early 1990s, Republican and Democrats were almost entirely in sync with how they felt about immigrants' contributions to the country, but as Democrats have become more progressive, Republicans have become more conservative.

Among 2016 voters who said "the most important issue facing the country" was immigration, they heavily favored Trump — 64 percent to 32 percent — according to the exit polls.

Republican pollster Whit Ayres believes that immigration is politically potent not so much on its own, but as symbolic of broader emotional issues that affect the GOP base.

"For opponents of immigration, the issue taps into economic pressures that could damage the blue-collar middle class, as well as fears that we're losing our culture — a country that's spoken English since its founding is becoming bilingual," he explained. "Don't underestimate ... the frustration of many Trump voters that we are losing our country. And that we are fundamentally changing it in ways that are unlike anything we've had in the past."

John Sides, a political science professor at George Washington University, conducted a survey after the 2016 election where he interviewed the same voters he had spoken with in 2012 — so he knew how they felt about immigration and he also knew how they had voted.

"One of the reasons why Trump was able to win ... was by using the issue of immigration to pull some white Obama voters over to his side," explained Sides. His research found that about a quarter to a third of white Obama voters in 2012 had fairly conservative positions on immigration.

"We were able to show among white voters there were only a handful of things that were more strongly related to their choice between Trump and Clinton than their choice between Obama and Romney, and those things had to do with their views of race, and their views of immigration, and their views of Muslims," Sides said.

What history tells us

So maybe heated rhetoric alone does not turn out voters, but Lopez says policy changes might, such as when the DACA program was first introduced the summer before President Obama's re-election.

"Obama in 2012 was under this cloud of being a 'deporter-in-chief,' — at least many Latino leaders had described him as such," said Lopez. "So when he does DACA many analysts say that was just enough the motivator to get many Hispanics who were perhaps on the fence about voting out to vote."

But even if there was a post-DACA bump, it was a minor bump.

Chris Zepeda-Millán, a political scientist at the University of California, Berkeley, says history proves that Latinos are more likely to mobilize against a legislative threat than for legislative action. He points to the mass Latino mobilization in 2006 because of the Sensenbrenner bill, which threatened to make it a federal crime to aid someone who entered the country illegally.

"Latinos tend to come and out vote, and immigrants, when there's anti-immigrant legislation on the ballot," said Zepeda-Millán. "We saw this in California. We've seen it in other states as well. When there's anti-immigrant legislation looming, Latinos tend to come out at higher rates."

A similar thing happened in California in the 1990s when Republicans backed Proposition 187, a ballot measure to deny public services to people in the country illegally.

Midterm consequences

The key difference between Donald Trump's election and the upcoming midterms is that it's a fundamentally different political landscape. This November, elections will be held in discrete districts.

The Republican pollster Whit Ayres points out that much of how immigration is discussed in a local contest comes down to the demographic context of the local area. And in many key suburban swing districts, immigration may not be as much of a lighting rod in either direction.

Many of these analysts on the topic of immigration say that Republicans could benefit in those areas by merely getting the issue off the table. Any immigration solution, even if it's merely a short-term DACA fix, could suffice.

"Most voters don't list immigration as their number one voting issue," said Erickson-Hatalsky. "So, I think if Trump signs a deal that probably diffuses the issue politically, in general."

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