From Nate Silver’s FiveThirtyEight:
Trump’s Hardline Immigration Stance Got Him To The White House
SEP. 12, 2017 AT 5:59 AM
That may overwhelm the popularity of DACA as far as Republicans in Congress are concerned.
By Harry Enten and Perry Bacon Jr.
…A DACA-like bill could be approved by Congress. But there’s a big force in the way: Anti-immigration sentiment in the Republican Party. DACA may be popular, even among some Republicans, but hardline immigration policy has been growing as an animating force in GOP politics for years. It helped put Trump in the White House.
So looking only at the polling on DACA can be misleading if you’re trying to gauge the chances that the Republican-controlled Congress will replace the program. …
Immigration is similar to guns in that the Democratic position on many specific immigration policy questions is more popular than the Republican position, but Republicans hold their own on immigration more generally. Much of Trump’s immigration agenda doesn’t poll well: For instance, there isn’t broad support for building a border wall with Mexico, limiting legal immigration or ending DACA. However, recent surveys from George Washington University and Morning Consult found that Democrats and Republicans tend to poll evenly when it comes to which party is trusted more to handle immigration.
Additionally, immigration tends to be an issue that is more important to Republicans than Democrats. The 2016 national exit poll found that Trump beat Hillary Clinton by 31 percentage points among voters who said immigration was the most important issue facing the country. The 2016 Cooperative Congressional Election Study found that 73 percent of Trump voters said immigration was of “very high importance” to them, compared with 24 percent of Clinton voters. And despite Trump’s rhetoric on immigration and Latinos during the 2016 campaign, he probably did no worse among them than Mitt Romney did in 2012. (And he may have done slightly better.)
So even though DACA is popular, Republicans would be unlikely to face a backlash among their voters — even their more centrist ones — should they refuse to pass a replacement.
Indeed, Republican members of Congress could face a backlash if they pass one — in the form of primary challenges. In recent elections, a hardline stance on immigration has proved to be a winner in Republican primaries. It has been highly correlated with how well GOP senators have done against primary challenges — senators with more hardline positions have done better against primary challengers; those with more moderate views have done worse.
In 2016, moreover, immigration may have been the issue most responsible for Trump’s winning the Republican nomination. In every state with a caucus or primary exit poll, he did best among voters who said immigration was their top issue.